Attorney Docket No.112738.01289 P1671-WO2 METHODS OF PRODUCING 2,3,5,6-ALKYL-1,4-BENZOQUINONES PRIORITY INFORMATION [001] The application claims priority to, and the benefit of, PCT Application PCT/CN2022/117598 filed September 7, 2022, the entirety of which is incorporated by reference for all purposes. TECHNICAL FIELD [002] The application discloses methods useful for the synthesis of certain 2,3,5,6-alkyl-1,4- benzoquinone compounds, including 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione, and synthetic intermediates for the production thereof. BACKGROUND [003] 2,3,5,6-Alkyl-1,4-benzoquinone compounds and the use of these benzoquinones for the treatment of pervasive development disorders are described in U.S. Patent No.9,399,612. The use of 2,3,5,6-alkyl-1,4-benzoquinone compounds for the treatment of oxidative stress and inflammation has been described in PCT Application and WO 2018/191732. Recently, a certain 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione has also been described as a treatment for α-synucleinopathies and tauopathies, such as Parkinson’s disease and Amyotrophic Lateral Sclerosis (ALS) in U.S. Patent Nos.11,174,212 and 11,746,077 and PCT Application WO 2020/081879; and as a treatment for hemoglobinopathy or thalassemia in PCT Application WO 2021/077034. Methods of recrystallizing a certain 2,3,5-trimethyl-6- nonylcyclohexa-2,5-diene-1,4-dione have been described in U.S. Patent No. 11,667,596 and PCT Application WO 2020/081879. [004] Given the importance of these benzoquinone compounds, it is useful to provide methods and synthetic intermediates for their production, including methods producing the products in high yield and using minimal chromatography. BRIEF SUMMARY [005] In one aspect, a process is provided for the synthesis of a benzoquinone of Formula (I): 1 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof; wherein R ¹ , R ² , and R ³ are independently selected from C1-4alkyl; and R ⁴ is C _4-10 alkyl. [006] In certain embodiments, the process described herein may be accomplished with inexpensive and common reagents, which help to minimize or eliminate purification steps. For example under certain conditions, such as those described in PCT Application WO 2020/081879, the synthesis of 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione uses AgNO3 in the final step. The product was subjected to two isolations, which in addition to the high silver content, resulted in an inhomogeneous mixture. The advantageous process described herein assists in synthetic efficiency and easy scale-up, which helps to reduce production time, solvent consumption, and infrastructure. Further, as described herein, a flow chemistry process has been developed for the synthesis of a certain benzoquinone of Formula (I). Using flow chemistry conditions, the production of the benzoquinone can be accomplished efficiently and quickly under large-scale conditions to consistently afford the product in high yield and purity. [007] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, a mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (b.1) reducing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib) to afford an alkyl-substituted hydroquinone of Formula (Ic) or salt thereof: or (b.2) the alkyl- substituted hydroquinone of Formula (Ic) or salt thereof: 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 (c.1) oxidizing the alkyl-substituted hydroquinone of Formula (Ic) or salt thereof to afford the benzoquinone of Formula (I) or a stereoisomer, a mixture of stereoisomers, solvate, and/or hydrate thereof: ; wherein R ¹ , R ² , and R ³ R ⁴ is C _4-10 alkyl. In some or any embodiments, process Formula (I) comprises the steps of (b.1) and (c.1). In some or any embodiments, the process for synthesizing the compound of Formula (I) comprises the steps of (b.2) and (c.1). [008] Formula (Ia) and Formula (Ib) are drawn with a wavy line to indicate the compound can be the cis-isomer (the Z-isomer), the trans-isomer (the E-isomer), or a mixture of cis- and trans-isomers. The E- and Z-isomers are drawn as such and designated by (E-Ia) or (E-Ib) and (Z-Ia) or (Z-Ib), respectively. In one embodiment, step (b.1) is the reduction of a compound of Formula (Ia) and a compound of Formula (Ib) wherein the compound of Formula (Ia) and the compound of Formula (Ib) are both mixtures of the E- and Z-isomers, i.e., step (b.1) is the reduction of a mixture of compounds of Formula (E-Ia), (Z-Ia), (E-Ib), and (Z-Ib). In one embodiment, step (b.1) is the reduction of a mixture of a compound of Formula (E-Ia) and (Z- Ia). In one embodiment, step (b.1) is the reduction of a mixture of a compound of Formula (E- Ib) and (Z-Ib). In one embodiment, step (b.1) is the reduction of a mixture of compounds of Formula (E-Ia) and (E-Ib). In one embodiment, step (b.1) is the reduction of a mixture of compounds of Formula (Z-Ia) and (Z-Ib). [009] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, a mixture of stereoisomers, solvate, and/or hydrate thereof further comprises an (a.1) step before the (b.1) step: (a.1) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof and an aldehyde of Formula (If) to afford the alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib): or Attorney Docket No.112738.01289 P1671-WO2 further comprises an (a.2) step before the (b.2) step: (a.2) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof with an aldehyde of Formula (If) to afford the acetal of Formula (Id) or salt thereof: . [010] In one of Formula (Ia) and (Ib) wherein the compound of Formula (Ia) and (Ib) are both a mixture of E and Z-isomers, i.e., a mixture of compounds of Formula (Z-Ia), (E-Ia), (Z-Ib), and (E-Ib). In one embodiment, step (a.1) affords a mixture of a compound of Formula (Z-Ia) and (E-Ia). In one embodiment, step (a.1) affords a mixture of a compound of Formula (Z-Ib) and (E-Ib). In one embodiment, step (a.1) affords a mixture of compounds of Formula (Z-Ia) and (Z-Ib). In one embodiment, step (a.1) affords a mixture of compounds of Formula (E-Ia) and (E-Ib). [011] In some or any embodiments, the process for synthesizing an alkyl-substituted hydroquinone of Formula (Ic) or salt, stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (b.1) reducing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib) to afford the alkyl-substituted hydroquinone of Formula (Ic) or salt thereof: or (b.2) afford the alkyl- substituted hydroquinone of Formula (Ic) or salt, stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof: ; 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 wherein R ¹ , R ² , and R ³ are independently selected from C _1-4 alkyl; and R ⁴ is C _4-10 alkyl. In some or any embodiments, the process for synthesizing an alkyl-substituted hydroquinone of Formula (Ic) comprises the step of (b.1). In some or any embodiments, the process for synthesizing an alkyl-substituted hydroquinone of Formula (Ic) comprises the step of (b.2). [012] Purification of the benzoquinone of Formula (I) can be obtained by any method known to a person of skill in the art, including, but not limited to column chromatography, crystallization, titration, and distillation. In certain embodiments the benzoquinone of Formula (I) is further purified by crystallization in, for example, a solvent/anti-solvent system, for example an alcohol/water system. In one embodiment, the solvent is an alcohol, including, but not limited to, methanol, ethanol, n-propanol, isopropanol, and n-butanol. In one embodiment, the solvent is a C3-C7 ketone, for example, acetone, methyl ethyl ketone, or propanone. In one embodiment, the benzoquinone of Formula (I) is further purified by crystallization in an isopropanol/water system. In one embodiment, the benzoquinone of Formula (I) is further purified by crystallization in an acetone/water system. Purification via crystallization of a certain benzoquinone, 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione, is described in WO 2020/081879. [013] In some embodiments of the process described herein, the benzoquinone of Formula (I) is not a solvate or hydrate. [014] In certain embodiments, the benzoquinone of Formula (I) is the benzoquinone compound 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione. [015] In another aspect, provided is a process for synthesizing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib) comprising an (a.1) step: (a.1) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof and an aldehyde of Formula (If) to afford the alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or the alkenyl-substituted quinone of Formula (Ib): . [016] In another aspect, provided is a process for synthesizing an acetal of Formula (Id) or salt thereof comprising an (a.2) step: 5 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 (a.2) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof with an aldehyde of Formula (If) to afford the acetal of Formula (Id) or salt thereof: . [017] In another using flow chemistry conditions. In some or any embodiments described herein, the steps of (a.1), (b.1), and/or (c.1) are conducted using flow chemistry, for example as described in FIG.3, FIG.4, and/or FIG.5. In one embodiment, the process for synthesizing a benzoquinone of Formula (I) comprises the steps of (b.1) and (c.1) wherein both steps are conducted using flow chemistry as described herein, for example in FIG. 4 and FIG. 5. In one embodiment, the process for synthesizing a benzoquinone of Formula (I) comprises the steps of (a.1), (b.1) and (c.1) wherein the steps are conducted using flow chemistry as described herein, for example in FIG. 3, FIG. 4, and FIG. 5. In some or any embodiments, the process for synthesizing an alkyl-substituted hydroquinone of Formula (Ic) comprises the step of (b.1) using flow chemistry. In some or any embodiments, the process for synthesizing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib) comprises the step of (a.1) using flow chemistry. [018] In some or any embodiments, a benzoquinone of Formula (I) is synthesized via a flow chemistry process that comprises steps (a.1), (b.1), and (c.1), for example as described in FIG. 3, FIG. 4, and FIG. 5. In some or any embodiments, a benzoquinone of Formula (I) is synthesized via a flow chemistry process that comprises steps (b.1) and (c.1), for example as described in FIG.4 and FIG.5. [019] In some or any embodiments, the step of (a.1) is conducted using flow chemistry, for example as described in FIG. 3, wherein a solution comprising a trialkylhydroquinone of Formula (Ie) and an aldehyde of Formula (If) in an organic solvent are mixed together first in a static mixer and then transferred to a high temperature oven for the condensation reaction to afford the alkenyl-substituted hydroquinone of Formula (Ia) and/or the alkenyl-substituted quinone of Formula (Ib). In one embodiment, the condensation reaction is conducted for about 70 minutes at a temperature between about 160 °C and 180 °C. 6 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [020] In some or any embodiments, the step of (b.1) is conducted using flow chemistry, for example as described in FIG. 4, wherein a solution of alkenyl-substituted hydroquinone of Formula (Ia) and/or the alkenyl-substituted quinone of Formula (Ib) is contacted with a catalyst and hydrogen in a tubular reactor to afford an alkyl-substituted hydroquinone of Formula (Ic). In one embodiment, the reaction takes place at a temperature between about 15 °C and 40 °C. In one embodiment, the catalyst is Pd(OH) ₂ /Al ₂ O ₃ . [021] In some or any embodiments, the step of (c.1) is conducted using flow chemistry, for example as described in FIG. 5, wherein a solution of alkyl-substituted hydroquinone of Formula (Ic) is oxidized in the presence of diluted O2 in stainless steel reactor tubing to afford a benzoquinone of Formula (I). In one embodiment, the internal diameter of the reactor tubing is between about 1/16 ^th and 1/8 ^th of an inch, preferably about 1/8 ^th of an inch. In one embodiment the diluted O2 is 5% O2 in N2. [022] In some or any embodiments, a benzoquinone of Formula (I) is synthesized in a flow chemistry process comprising the steps of: a) mixing together a solution comprising a trialkylhydroquinone of Formula (Ie), an aldehyde of Formula (If), and an acid catalyst in an organic solvent in a static mixer and transferring the solution to a high temperature oven to afford a solution comprising the acid catalyst and the alkenyl-substituted hydroquinone of Formula (Ia) and/or the alkenyl-substituted quinone of Formula (Ib) in the organic solvent; b) transferring the solution of acid catalyst and the alkenyl-substituted hydroquinone of Formula (Ia) and/or the alkenyl-substituted quinone of Formula (Ib) in the organic solvent to a vessel and removing the acid catalyst by aqueous wash; c) directly transferring the solution of alkenyl-substituted hydroquinone of Formula (Ia) and/or the alkenyl-substituted quinone of Formula (Ib) in the organic solvent to a tubular reactor wherein the alkenyl-substituted hydroquinone of Formula (Ia) and/or the alkenyl-substituted quinone of Formula (Ib) is reduced in the presence of a catalyst and hydrogen to afford an alkyl-substituted hydroquinone of Formula (Ic) in the organic solvent; d) filtering the organic solvent comprising the alkyl-substituted hydroquinone of Formula (Ic) to remove catalyst and directly transferring the solution of alkyl-substituted hydroquinone of Formula (Ic) to stainless steel reactor tubing where in the presence of diluted O ₂ , the alkyl-substituted hydroquinone of Formula (Ic) is oxidized to a benzoquinone of Formula (I); and 7 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 e) isolating the benzoquinone of Formula (I). [023] In one embodiment, the organic solvent is a C ₂ -C ₈ ether, including, but not limited to dimethyl ether, methyl-t-butyl ether (MTBE), and cyclopentyl methyl ether (CPME). In one embodiment, the organic solvent is cyclopentyl methyl ether (CPME). [024] In another aspect, a compound of Formula (Ia) or a salt thereof, Formula (Ib), and Formula (Id) or a salt thereof are provided: or a wherein R ¹ , R ² , and R ³ are independently selected from C _1-4 alkyl; and R ⁴ is C4-10alkyl. [025] In one embodiment, the compound of Formula (Ia) is a compound of Formula (E-Ia): . [026] In one embodiment, the (Ia) is a compound of Formula (Z-Ia): . [027] In one embodiment, the (Ib) is a compound of Formula (E-Ib): . [028] In one embodiment, the (Ib) is a compound of Formula (Z-Ib): . BRIEF OF FIGURES [029] FIG.1 is the ¹ NMR spectrum of Compound 1 prepared as described in Example 1. 8 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [030] FIG.2 is the ¹ NMR spectrum of Compound 1 prepared as described in Example 2. [031] FIG.3 is a schematic for the condensation of step (a.1) using flow chemistry. [032] FIG.4 is a schematic for the reduction of step (b.1) using flow chemistry. [033] FIG.5 is a schematic for the oxidation of step (c.1) using flow chemistry. DETAILED DESCRIPTION [034] Provided herein are methods useful for the synthesis of benzoquinone compounds of Formula (I) and stereoisomers, mixtures of stereoisomers, solvates, and/or hydrates thereof. Further provided are synthetic intermediates useful in the synthesis of benzoquinone compounds of Formula (I) and stereoisomers, mixtures of stereoisomers, solvates, and/or hydrates thereof. In certain embodiments, the benzoquinone of Formula (I) is the benzoquinone compound 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione. Also described herein are conditions for the synthesis of a benzoquinone compound of Formula (I) using flow chemistry conditions. Definitions [035] The abbreviations used herein have their conventional meaning within the chemical and biological arts, unless otherwise specified. [036] Reference to “about” a value or parameter herein includes (and describes) variations that are directed to that value or parameter per se. For example, description referring to “about X” includes description of “X.” As used herein, and unless otherwise specified, the terms “about” and “approximately,” when used in connection with temperatures, doses, amounts, or weight percent of ingredients of a composition or a dosage form, mean a dose, amount, or weight percent that is recognized by those of ordinary skill in the art to provide a pharmacological effect equivalent to that obtained from the specified dose, amount, or weight percent. Specifically, the terms “about” and “approximately,” when used in this context, contemplate a temperature, dose, amount, or weight percent within 15%, within 10%, within 5%, within 4%, within 3%, within 2%, within 1%, or within 0.5% of the specified temperature, dose, amount, or weight percent. [037] A reference to a range of values or parameters that are “between” two values or parameters is inclusive of the endpoints of the range unless specified otherwise. [038] The terms “a” and “an,” as used in herein mean one or more, unless context clearly dictates otherwise. 9 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [039] “Pure” or “purified” as described herein, refers to the purity of a given compound. For example, a compound is “purified” when the given compound is a major component of the composition, i.e., at least 50% w/w pure. Thus, “purified” embraces at least 50% w/w purity, at least 60% w/w purity, at least 70% purity, at least 80% purity, at least 85% purity, at least 90% purity, at least 92% purity, at least 94% purity, at least 96% purity, at least 97% purity, at least 98% purity, at least 99% purity, at least 99.5% purity, and at least 99.9% purity, wherein “substantially pure” embraces at least 95% purity, at least 96% purity, at least 97% purity, at least 98% purity, at least 99% purity, at least 99.5% purity, and at least 99.9% purity. [040] “Diastereomerically enriched” means that one diastereomer is in excess of the other diastereomer. [041] “Diastereomerically pure” refers to a compound whose diastereomeric purity is at least about 90%, about 95%, about 99%, or even 100% pure. [042] “Alkyl” is a straight or branched chain or a cyclic saturated aliphatic hydrocarbon group. In certain embodiments, the alkyl contains from 1 to about 40 carbons, more generally from 1 to about 10 carbons. In certain embodiments, the alkyl is C1-C2, C1-C3, C1-C4, C4-C10, C5-C10, C6-C10, C7-C10, C8-C10, or C9-C10 (i.e., the alkyl chain can be 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbons in length) _. The specified ranges as used herein indicate an alkyl group with a length of each member of the range described as an independent species. In one embodiment, “alkyl” is a straight chain. In an alternative embodiment, “alkyl” is a branched chain. In an alternative embodiment, “alkyl” is a cyclic alkyl. For example, the term "C1-C4 alkyl" is intended to embrace methyl (Me), ethyl (Et), propyl (Pr), n-propyl (nPr), isopropyl (iPr), butyl (Bu), n- butyl (nBu), isobutyl (iBu), sec-butyl (sBu), t-butyl (tBu), cyclopropyl (cyclPr), cyclobutyl (cyclBu), cyclopropyl-methyl (cyclPr-Me) and methyl-cyclopropane (Me-cyclPr), where the C1-C4 alkyl groups can be attached via any valence on the C1-C4 alkyl groups. [043] “C ₁ -C ₈ alcohol” refers to a straight/branched and/or cyclic/acyclic alcohol having any of the number of carbons within the range, and the range is specifically intended to independently disclose each compound within the range. Examples of a C1-C8 alcohol include, but are not limited to, methanol, ethanol, n-propanol, isopropanol, isobutanol, hexanol, and cyclohexanol. [044] “C ₂ -C ₈ ether” refers to a straight/branched and/or cyclic/acyclic ether having any of the number of carbons within the range, and the range is specifically intended to independently disclose each compound within the range. Examples of a C ₂ -C ₈ ether include, but are not 10 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 limited to, dimethyl ether, diethyl ether, di-isopropyl ether, di-n-butyl ether, methyl-t-butyl ether (MTBE), tetrahydrofuran, cyclopentyl methyl ether (CPME), and dioxane. [045] “C3-C7 ketone” refers to a straight/branched and/or cyclic/acyclic ketone having any of the number of carbons within the range, and the range is specifically intended to independently disclose each compound within the range. Examples of C3-C7 ketone include, but are not limited to, acetone, methyl ethyl ketone, propanone, butanone, methyl isobutyl ketone, methyl butyl ketone, and cyclohexanone. [046] “C ₂ -C ₇ nitrile” refers to a nitrile having any of the number of carbons within the range, and the range is specifically intended to independently disclose each compound within the range. Examples of C ₂ -C ₇ nitrile include, but are not limited to, acetonitrile and propionitrile. [047] “C3-C7 ester” refers to a straight/branched and/or cyclic/acyclic ester having any of the number of carbons within the range, and the range is specifically intended to independently disclose each compound within the range. Examples of C3-C7 ester include, but are not limited to, ethyl acetate, propyl acetate, and n-butyl acetate. [048] “C1-C2 chlorocarbon” refers to a chlorocarbon with 1-2 carbons, with any number of chloro atoms that is chemically feasible. The C1-C2 chlorocarbon includes, but is not limited to, chloroform, dichloromethane (DCM), carbon tetrachloride, 1,2-dichloroethane, and tetrachloroethane, [049] “Flow chemistry” is a process wherein one or more chemical reactions are conducted in a continuously flowing stream, in one embodiment, via one or more reactor tubes, flow reactors, and/or tubular reactors. One or more reactants are contacted in the reactor tubes, flow reactors, and/or tubular reactors to afford a product, which is then collected at an outlet of the reactor tubes, flow reactors, and/or tubular reactors. In one embodiment, the flow reactor is a fixed-bed flow reactor. [050] While the compounds described herein can occur and can be used as the neutral (non- salt) compound, the description is intended to embrace all salts of the compounds described herein, as well as methods of using such salts of the compounds. In some embodiments, the salts of the compounds comprise pharmaceutically acceptable salts. Pharmaceutically acceptable salts are those salts which can be administered as drugs or pharmaceuticals to humans and/or animals and which, upon administration, retain at least some of the biological activity of the free compound (non-ionic compound or non-salt compound). The desired salt of a basic compound may be prepared by methods known to those of skill in the art by treating the compound with an acid. In some embodiments, inorganic acids include, but are not limited 11 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 to, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, and phosphoric acid. In some embodiments, organic acids include, but are not limited to, formic acid, acetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid, maleic acid, malonic acid, succinic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, sulfonic acids, and salicylic acid. Salts of basic compounds with amino acids, such as aspartate salts and glutamate salts, can also be prepared. [051] The desired salt of an acidic compound can be prepared by methods known to those of skill in the art by treating the compound with a base. In some embodiments, inorganic salts of acid compounds include, but are not limited to, alkali metal and alkaline earth salts, such as sodium salts, potassium salts, magnesium salts, and calcium salts; ammonium salts; and aluminum salts. In some embodiments, organic salts of acid compounds include, but are not limited to, procaine, dibenzylamine, N-ethylpiperidine, N,N-dibenzylethylenediamine, and triethylamine salts. Salts of acidic compounds with amino acids, such as lysine salts, can also be prepared. [052] Any compound used in or formed by the processes described herein may form a solvate with solvents (including water). Therefore, in one non-limiting embodiment, the process affords a solvated form of a compound. The term “solvate” refers to a molecular complex of a compound of the present invention (including a salt thereof) with one or more solvent molecules. Non-limiting examples of solvent are water, ethanol, dimethyl sulfoxide, acetone, and other common organic solvents. The term “hydrate” refers to a molecular complex comprising a compound as described herein and water. Solvates in accordance with this disclosure include those wherein the solvent may be isotopically substituted, e.g. D2O, acetone- d6, and DMSO-d6. A solvate can be in a liquid or solid form. [053] Included herein, when chemically relevant, are all stereoisomers of the compounds, including diastereomers and enantiomers. Also included are mixtures of possible stereoisomers in any ratio, including, but not limited to, racemic mixtures. Unless stereochemistry is explicitly indicated in a structure, the structure is intended to embrace all possible stereoisomers of the compound depicted. If stereochemistry is explicitly indicated for one portion or portions of a molecule, but not for another portion or portions of a molecule, the structure is intended to embrace all possible stereoisomers for the portion or portions where stereochemistry is not explicitly indicated. A wavy line in Formula (Ia) and Formula (Ib) indicates that the compound is the cis-isomer (the Z-isomer), the trans-isomer (the E-isomer), or a mixture of the cis- and 12 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 trans-isomer. When it is intended for the compound of Formula (Ia) or Formula (Ib) to be the cis- or trans-isomer, the compound is drawn as such. [054] The description of compounds herein also includes all isotopologues, in some embodiments, partially deuterated or perdeuterated analogs of all compounds herein. [055] “Oxidation” and “oxidation step” embrace the transformation of a compound comprising a benzene-1,4-diol to a compound comprising benzoquinone. This transformation is accomplished with an oxidizer. In some embodiments, the oxidizer is selected from the group consisting of ceric ammonium nitrate, iron(III) nitrate, iron(III) sulfate, iron(III) tartrate, iron(III) acetate, iron(III) citrate, iron(III) phosphate, and/or an iron(III) halide. In some or any embodiments, the oxidizer is Fe(III)Cl ₃ . In some embodiment, the oxidizer is oxygen (pure or diluted). [056] In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (Ie), R ¹ , R ² , and R ³ are independently a straight C1-4alkyl chain. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (Ie), R ¹ , R ² , and R ³ are independently selected from C1-2alkyl, C2-4alkyl, and C3-4alkyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (Ie), R ¹ , R ² , and R ³ are each methyl. [057] In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (Ie), R ⁴ is a straight C4- ₁₀ alkyl chain. In alternative embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (Ie), R ⁴ is a branched C _4-10 alkyl chain. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (If), R ⁴ is a hexyl group, including, but not limited to n-hexyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (If), R ⁴ is a heptyl group, including, but not limited to n-heptyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (If), R ⁴ is an octyl group, including, but not limited n-octyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (If), R ⁴ is a nonyl group, including, but not limited n-nonyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (If), R ⁴ is a decyl group, 13 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 including, but not limited n-decyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), Formula (Id), or Formula (If), R ⁴ is a undecyl group, including, but not limited n-undecyl. [058] In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently a straight C _1-4 alkyl chain and R ⁴ is a straight C _4-10 alkyl chain. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C _1- 2alkyl and R ⁴ is C4-7alkyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C1-2alkyl and R ⁴ is C7-10alkyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C2-4alkyl and R ⁴ is C4-7alkyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C2-4alkyl and R ⁴ is C7-10alkyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C3-4alkyl and R ⁴ is C4-7alkyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C3-4alkyl and R ⁴ is C _7-10 alkyl. [059] In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is C4-7alkyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is C7-10alkyl. [060] In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is a straight C4-7alkyl chain. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is a straight C7-10alkyl chain. [061] In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and 14 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 R ⁴ is n-hexyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ is methyl, R ² is methyl, R ³ is t-butyl, and R ⁴ is n-hexyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is n-heptyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ is methyl, R ² is t-butyl, R ³ is t-butyl, and R ⁴ is n-heptyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is n-octyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is n-nonyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is n-decyl. In certain embodiments, including the processes described herein, in Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each methyl and R ⁴ is n-undecyl. [062] In certain embodiments, including the processes described herein, the compound of Formula (Ia) is selected from: , 15 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [063] In certain embodiments, including the processes described herein, the compound of Formula (Ia) is of the formula: or a salt thereof. [064] In certain embodiments, processes herein, the compound of Formula (Ib) is of the formula: , of Formula (Ib) is of the formula: . [066] In certain embodiments, described herein, the compound of Formula (Ia) is selected from: , , Attorney Docket No.112738.01289 P1671-WO2 processes of Formula (Ia) is selected from: , [068] In certain embodiments, including the processes described herein, the compound of Formula (Ia) is of the formula: or a salt thereof. [069] In certain embodiments, including the processes described herein, the compound of Formula (Ia) is of the formula: or a salt thereof. 17 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [070] In certain embodiments, including the processes described herein, the compound of Formula (Ib) is of the formula: . of Formula (Ib) is selected from: , of Formula (Ib) is of the formula: . 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [073] In certain embodiments, including the processes described herein, the compound of Formula (Ib) is of the formula: . [074] In certain embodiments, herein, the compound of Formula (Id) is of the formula: , , [075] In certain embodiments, including the processes described herein, the compound of Formula (Id) is of the formula: 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 or salt thereof. [076] In certain embodiments, the processes described herein afford a compound of Formula (I) selected from: . Preparation of Compounds [077] The methods described herein provide advantages for the synthesis of benzoquinone compounds, including 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione, for example, for obtaining high yields and/or purity of product, and/or by allowing for minimal purification steps. [078] Reaction times and reaction conditions (e.g., temperature, atmosphere, etc.) will vary and may be determined by reference to the examples and disclosure provided herein, as well as routine experimentation and consultation of the relevant literature when necessary. [079] The compounds disclosed herein can be prepared from readily available starting materials; non-limiting exemplary methods are described in the Examples. It will be appreciated by one of ordinary skill in the art that where typical or preferred process conditions (i.e., reaction temperatures, times, mole ratios of reactants, solvents, pressures, etc.) are given, other process conditions can also be used unless otherwise stated. [080] All processes described herein can be performed in a suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of an example, or exemplary language (for example, “such as”), is intended merely to better illustrate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. 20 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 Step (a.1) [081] In one embodiment, the condensation of step (a.1) is conducted in the presence of an acid catalyst. In certain embodiments, the acid catalyst is a sulfonic acid, including, but not limited to methanesulfonic acid, benzenesulfonic acid, and para-toluenesulfonic acid. In certain embodiments, the acid catalyst is para-toluenesulfonic acid monohydrate or benzenesulfonic acid monohydrate. In one embodiment, the acid catalyst is para-toluenesulfonic acid monohydrate. [082] In certain embodiments, the condensation of step (a.1) is conducted at a temperature between about 80 °C and about 120 °C, between about 85 °C and about 115 °C, or between about 90 °C and about 110 °C. In certain embodiments, the condensation of step (a) is conducted for at least about 5 hours, at least about 6 hours, at least about 7 hours, at least about 8 hours, at least about 9 hours, at least about 10 hours, or more. In one embodiment, the condensation is conducted at a temperature between about 80 °C and about 120 °C and is conducted for at least about 6 hours. [083] In one embodiment, in step (a.1), the molar ratio of the aldehyde of Formula (If) and the trialkylhydroquinone of Formula (Ie) is about 1:1 or about 1.2:1. [084] In certain embodiments, the condensation of step (a.1) is conducted in a C ₂ -C ₈ ether, including, but not limited to dimethyl ether, methyl-t-butyl ether (MTBE), and cyclopentyl methyl ether (CPME). In one embodiment, the condensation of step (a.1) is conducted in cyclopentyl methyl ether (CPME). [085] The condensation of step (a.1) affords a compound of Formula (Ia), a compound of Formula (Ib), or a mixture thereof. In one embodiment, step (a.1) affords a mixture of a compound of Formula (a1) and a compound of Formula (Ib) wherein both compounds are mixtures of E and Z isomers, i.e., step (a.1) affords a mixture of compounds of Formula (E-Ia), (Z-Ia), (E-Ib), and (Z-Ib). In certain embodiments, the ratio by weight of Formula (Ia) to Formula (Ib) wherein Formula (Ia) is a mixture of E and Z isomers and Formula (Ib) is a mixture of E and Z isomers is about 100:0, about 99:1, about 95:5: about 90:10, about 85:15, about 80:20, about 75:25, about 70:30, about 65:35, about 60:40, about 55:45, about 50:50, about 45:55, about 40:60, about 35:65, about 30:70, about 25:75, about 20:80, about 15:85, about 10:90, about 5:95, about 1:99, or about 0:100. In one embodiment, the ratio by weight of Formula (Ia) to Formula (Ib) wherein Formula (Ia) is a mixture of E and Z isomers and Formula (Ib) is a mixture of E and Z isomers is between about 100:0 to 70:30. In one embodiment, the ratio by weight of Formula (Ia) to Formula (Ib) wherein Formula (Ia) is a mixture of E and Z 21 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 isomers and Formula (Ib) is a mixture of E and Z isomers is between about 100:0 to 95:5. In one embodiment, the ratio by weight is determined by HPLC, LCMS, or ¹ HNMR. [086] In one embodiment, step (a.1) affords a mixture of a compound of Formula (E-Ia) and (Z-Ia). In one embodiment, step (a.1) affords a mixture of a compound of Formula (E-Ib) and (Z-Ib). In certain embodiments, the ratio by weight of the Z- to E-isomer is about 100:0, about 99:1, about 95:5: about 90:10, about 85:15, about 80:20, about 75:25, about 70:30, about 65:35, about 60:40, about 55:45, about 50:50, about 45:55, about 40:60, about 35:65, about 30:70, about 25:75, about 20:80, about 15:85, about 10:90, about 5:95, about 1:99, or about 0:100. In one embodiment, the ratio by weight of the Z-isomer to the E-isomer is between about 0:100 to 30:70. In one embodiment, the ratio by weight is determined by ¹ HNMR. [087] In one embodiment, step (a.1) affords a mixture of a compound of Formula (E-Ia) and (E-Ib). In certain embodiments, the ratio by weight of Formula (E-Ia) to Formula (E-Ib) is about 100:0, about 99:1, about 95:5: about 90:10, about 85:15, about 80:20, about 75:25, about 70:30, about 65:35, about 60:40, about 55:45, about 50:50, about 45:55, about 40:60, about 35:65, about 30:70, about 25:75, about 20:80, about 15:85, about 10:90, about 5:95, about 1:99, or about 0:100. In one embodiment, the ratio by weight of Formula (E-Ia) to Formula (E-Ib) is between about 100:0 to 70:30. In one embodiment, the ratio by weight of Formula (E-Ia) to Formula (E-Ib) is a mixture of E and Z isomers is between about 100:0 to 95:5. In one embodiment, the ratio by weight is determined by ¹ HNMR. [088] In an alternative embodiment, step (a.1) affords a mixture of compounds of Formula (Z-Ia) and (Z-Ib). [089] In certain embodiments, the compound of Formula (Ia), the compound of Formula (Ib), or the mixture thereof is used directly in step (b.1) without further purification. Step (a.2) [090] In one embodiment, the acetal formation of step (a.2) is conducted under acidic conditions. In one embodiment, step (a.2) is conducted in a solvent system comprising (i) an aqueous acid and (ii) a C ₃ -C ₇ ester. In an alternative embodiment, step (a.2) is conducted in a solvent system comprising (i) an aqueous acid; (ii) a second aqueous acid that is different from the aqueous acid in (i); and (iii) a C ₃ -C ₇ ester. [091] Non-limiting examples of aqueous acids include, but are not limited to, perchloric acid, hydrochloric acid, hydrobromic acid, acetic acid, sulfuric acid, citric acid, nitric acid, and 22 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 phosphoric acid. Non-limiting examples of a C ₃ -C ₇ esters include, but are not limited to, ethyl acetate, isopropyl acetate, and butyl acetate. [092] In one embodiment, the solvent system comprises (i) an aqueous acid selected from acetic acid, phosphoric acid, and citric acid and (ii) a C ₃ -C ₇ ester. In one embodiment, the solvent system comprises (i) acetic acid and (ii) a C3-C7 ester selected from ethyl acetate, isopropyl acetate, and butyl acetate. In one embodiment, the solvent system comprises (i) acetic acid and (ii) isopropyl acetate. [093] In one embodiment, the solvent system comprises (i) an aqueous acid selected from acetic acid, phosphoric acid, and citric acid; (ii) an aqueous acid selected from perchloric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, and nitric acid; and (iii) a C ₃ -C ₇ ester selected from ethyl acetate, isopropyl acetate, and butyl acetate. In one embodiment, the solvent system comprises (i) acetic acid; (ii) an aqueous acid selected from perchloric hydrochloric acid, hydrobromic acid, sulfuric acid, and nitric acid; and (iii) a C3-C7 ester selected from ethyl acetate, isopropyl acetate, and butyl acetate. In one embodiment, the solvent system comprises (i) acetic acid; (ii) hydrochloric acid; and (iii) a C3-C7 ester selected from ethyl acetate, isopropyl acetate, and butyl acetate. In one embodiment, the solvent system comprises (i) acetic acid; (ii) hydrochloric acid; and (iii) isopropyl acetate. [094] In one embodiment, in step (a.2), the aldehyde of Formula (If) is in excess of the trialkylhydroquinone of Formula (Ie). In one embodiment, the molar ratio of the aldehyde of Formula (If) and the trialkylhydroquinone of Formula (Ie) is greater than about 2:1, greater than about 2.5:1, or greater than about 3:1. [095] In certain embodiments, step (a.2) is conducted for at least about 8 hours, at least about 10 hours, at least about 12 hours, at least about 14 hours, at least about 16 hours or more. In one embodiment, step (a.2) is conducted for about 16 hours. [096] In certain embodiments, the acetal of Formula (Id) has (2S,4R)-stereochemistry. In certain embodiments, the acetal has (2R,4S)-stereochemistry. In certain embodiments, the acetal is a mixture of acetal diastereomers with (2S,4R)- and (2R,4S)-stereochemistry. In certain embodiments, the mixture is approximately 50:50 by weight (2S,4R)- and (2R,4S)- diastereomers. [097] In certain embodiments, the acetal of Formula (Id) is a diastereomerically enriched mixture of diastereomers wherein the (2S,4R)-diastereomer is in excess of the (2R,4S)- diastereomer. In one embodiment, the enriched mixture is approximately 60:40, 70:30, 80:20, 90:10, 95:5, 98:2, or 99:1 by weight the (2S,4R)-diastereomer to the (2R,4S)-diastereomer. In 23 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 certain embodiments, the mixture of diastereomers is about 90:10, about 95:5, about 98:2, or about 99:1 by weight the (2S,4R)-diastereomer to the (2R,4S)-diastereomer. In one embodiment, the acetal is a diastereomerically pure acetal with (2S,4R)-stereochemistry. In alternative embodiments, the mixture of diastereomers is approximately 60:40, 70:30, 80:20, 90:10, 95:5, 98:2, or 99:1 by weight the (2R,4S)-diastereomer to the (2S,4R)-diastereomer. [098] In certain embodiments, the compound of Formula (Id) is used directly in step (b.2) without further purification. Step (b.1) [099] In certain embodiments, the reduction of step (b.1) is conducted under catalytic hydrogenation conditions, including but not limited to, hydrogenation in the presence of platinum, palladium, ruthenium, or nickel. In certain embodiments, the catalyst is Pd/C, Pt/C, Pd(OH)2/C, PtO2, Pd(OH)2/Al2O3, Raney Nickel, Ru/CaCO3, and Pd/CaCO3. In an alternative embodiment, the catalyst is Pd/Al2O3. [100] In one embodiment, the amount of catalyst is between about 0.1% and 20% by weight of the amount of Formula (Ia) and/or Formula (Ib). In certain embodiments, the amount of catalyst is between about 0.5% and 20%, between about 1% and 20%, between about 5% and 15%, or between about 8% and 12% by weight of the amount of Formula (Ia) and/or Formula (Ib). In one embodiment, the amount of catalyst is about 10% by weight of the amount Formula (Ia) and/or Formula (Ib). In one embodiment, the amount of the catalyst is at least about 0.1%, at least about 0.5%, at least about 1%, at least about 3%, at least about 5%, at least about 8%, at least about 10%, at least about 12%, at least about 15%, or at least about 20% by weight of the amount of Formula (Ia) and/or Formula (Ib). [101] In one embodiment, the catalyst is Pd/C and the amount of Pd/C is between about 0.1% and 20% by weight of the amount of Formula (Ia) and/or Formula (Ib). In certain embodiments, the catalyst is Pd/C and the amount of Pd/C is between about 0.5% and 20%, between about 1% and 20%, between about 5% and 15%, or between about 8% and 12% by weight of the amount of Formula (Ia) and/or Formula (Ib). In one embodiment, the amount of Pd/C is about 10% by weight of the amount of Formula (Ia) and/or Formula (Ib). In one embodiment, the catalyst is Pd/C and the amount of Pd/C is at least about 0.1%, at least about 0.5%, at least about 1%, at least about 3%, at least about 5%, at least about 8%, at least about 10%, at least about 12%, at least about 15%, or at least about 20% by weight of the amount Formula (Ia) and/or Formula (Ib). 24 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [102] In one embodiment, the catalyst is Pd(OH) ₂ /Al ₂ O ₃ and the amount of Pd(OH) ₂ /Al ₂ O ₃ is between about 0.1% and 20% by weight of the amount of Formula (Ia) and/or Formula (Ib). In certain embodiments, the catalyst is Pd(OH)2/Al2O3 and the amount of Pd(OH)2/Al2O3 is between about 0.5% and 20%, between about 1% and 20%, between about 5% and 15%, or between about 8% and 12% by weight of the amount of Formula (Ia) and/or Formula (Ib). In one embodiment, the amount of Pd(OH) ₂ /Al ₂ O ₃ is about 4% by weight of the amount of Formula (Ia) and/or Formula (Ib). In one embodiment, the catalyst is Pd(OH)2/Al2O3 and the amount of Pd(OH) ₂ /Al ₂ O ₃ is at least about 1%, at least about 3%, at least about 4%, at least about 5%, at least about 8%, at least about 10%, at least about 15%, or at least about 20% by weight of the amount Formula (Ia) and/or Formula (Ib). [103] In certain embodiments, the reduction of step (b.1) is conducted in a C2-C8ether, including, but not limited to dimethyl ether, methyl-t-butyl ether (MTBE), and cyclopentyl methyl ether (CPME). In one embodiment, the reduction of step (b.1) is conducted in cyclopentyl methyl ether (CPME). In certain embodiments, the reduction of step (b.1) is conducted in a C1-C8alcohol, including, but not limited to methanol, ethanol, and isopropanol. [104] Alternative solvents for the reduction of step (b.1) include polar aprotic solvents, for example a C ₃ -C ₇ ketone, including, but not limited to acetone, propanone, and methyl isobutyl ketone, and a C3-C7nitrile, including, but not limited to acetonitrile (ACN) and propionitrile. In certain embodiments, DMF or DMSO are also used for the reduction of step (b.1). [105] In certain embodiments, the reduction of step (b.1) is conducted with the catalyst Pd(OH) ₂ /Al ₂ O ₃ in a C ₂ -C ₈ ether, including, but not limited to dimethyl ether, methyl-t-butyl ether (MTBE), and cyclopentyl methyl ether (CPME), and in the presence of AcOH to help stabilize the catalyst. In certain embodiments, the reduction of step (b.1) is conducted with the catalyst Pd(OH)2/Al2O3 in CPME and about 1 equivalence of AcOH to the amount of the starting material (Ie). [106] In certain embodiments, the reduction of step (b.1) is conducted at room temperature for at least about 12 hours, at least about 24 hours, at least about 36 hours, at least about 48 hours, or more. In one embodiment, the reduction of step (b.1) is conducted at room temperature between about 20 and 30 hours. In one embodiment, the reduction of step (b.1) is conducted at room temperature for about 26 hours. [107] In certain embodiments, the reduction of step (b.1) is the reduction of a compound of Formula (Ia) to afford a compound of Formula (Ic). In certain embodiments, the reduction of 25 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 step (b.1) is the reduction of a compound of Formula (Ib) to afford a compound of Formula (Ic). [108] The reduction of step (b.1) is the reduction of a compound of Formula (Ia), a compound of Formula (Ib), or a mixture thereof. In one embodiment, step (b.1) is the reduction of a mixture of a compound of Formula (a1) and a compound of Formula (Ib) wherein both compounds are mixtures of E and Z isomers, i.e., step (a.1) affords a mixture of compounds of Formula (E-Ia), (Z-Ia), (E-Ib), and (Z-Ib). In certain embodiments, the ratio by weight of Formula (Ia) to Formula (Ib) wherein Formula (Ia) is a mixture of E and Z isomers and Formula (Ib) is a mixture of E and Z isomers is about 100:0, about 99:1, about 95:5: about 90:10, about 85:15, about 80:20, about 75:25, about 70:30, about 65:35, about 60:40, about 55:45, about 50:50, about 45:55, about 40:60, about 35:65, about 30:70, about 25:75, about 20:80, about 15:85, about 10:90, about 5:95, about 1:99, or about 0:100. In one embodiment, the ratio by weight of Formula (Ia) to Formula (Ib) wherein Formula (Ia) is a mixture of E and Z isomers and Formula (Ib) is a mixture of E and Z isomers is between about 100:0 to 70:30. In one embodiment, the ratio by weight of Formula (Ia) to Formula (Ib) wherein Formula (Ia) is a mixture of E and Z isomers and Formula (Ib) is a mixture of E and Z isomers is between about 100:0 to 95:5. In one embodiment, the ratio by weight is determined by HPLC, LCMS, or ¹ HNMR. [109] In one embodiment, step (b.1) is the reduction of a mixture of a compound of Formula (E-Ia) and (Z-Ia). In one embodiment, step (b.1) is the reduction of a mixture of a compound of Formula (E-Ib) and (Z-Ib). In certain embodiments, the ratio by weight of the Z- to E-isomer is about 100:0, about 99:1, about 95:5: about 90:10, about 85:15, about 80:20, about 75:25, about 70:30, about 65:35, about 60:40, about 55:45, about 50:50, about 45:55, about 40:60, about 35:65, about 30:70, about 25:75, about 20:80, about 15:85, about 10:90, about 5:95, about 1:99, or about 0:100. In one embodiment, the ratio by weight of the Z-isomer to the E-isomer is between about 0:100 to 30:70. In one embodiment, the ratio by weight is determined by ¹ HNMR. [110] In one embodiment, step (b.1) is the reduction of a mixture of compounds of Formula (E-Ia) and (E-Ib). In certain embodiments, the ratio by weight of Formula (E-Ia) to Formula (E-Ib) is about 100:0, about 99:1, about 95:5: about 90:10, about 85:15, about 80:20, about 75:25, about 70:30, about 65:35, about 60:40, about 55:45, about 50:50, about 45:55, about 40:60, about 35:65, about 30:70, about 25:75, about 20:80, about 15:85, about 10:90, about 5:95, about 1:99, or about 0:100. In one embodiment, the ratio by weight of Formula (E-Ia) to 26 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 Formula (E-Ib) is between about 100:0 to 70:30. In one embodiment, the ratio by weight of Formula (E-Ia) to Formula (E-Ib) is between about 100:0 to 95:5. In one embodiment, the ratio by weight is determined by ¹ HNMR. [111] In an alternative embodiment, step (b.1) is the reduction of a mixture of compounds of Formula (Z-Ia) and (Z-Ib).In certain embodiments, the compound of Formula (Ic) is filtered to remove catalyst and used directly in step (c.1) without further purification. Step (b.2) [112] In certain embodiments, the hydrogenation of step (b.2) is conducted under catalytic hydrogenation conditions in an aqueous acid. In one embodiment, the hydrogenation is conducted in the presence of a platinum, palladium, nickel, rhodium, ruthenium, or iridium catalyst. In certain embodiments, the catalyst is Pd/C, Pd(OH)2/C, or PtO2. In one embodiment, the catalyst is Pd/C. In certain embodiments, the catalyst is Pd/Al2O3 or Pd(OH)2/Al2O3. In certain embodiments, the catalyst is Wilkinson’s catalyst (RhCl(PPh3)3), Ru/Al2O3, or Crabtree’s catalyst [C8H12IrP(C6H11)3C5H5N]PF6. [113] In one embodiment, the amount of catalyst is between about 0.1% and 20% by weight of the amount of Formula (Id). In certain embodiments, the amount of catalyst is between about 0.5% and 20%, between about 1% and 20%, between about 5% and 15%, or between about 8% and 12% by weight of the amount of Formula (Id). In one embodiment, the amount of catalyst is about 10% by weight of the amount of Formula (Id). In one embodiment, the amount of the catalyst is at least about 0.1%, at least about 0.5%, at least about 1%, at least about 3%, at least about 5%, at least about 8%, at least about 10%, at least about 12%, at least about 15%, or at least about 20% by weight of the amount of Formula (Id). [114] In one embodiment, the catalyst is Pd/C and the amount of Pd/C is between about 0.1% and 20% by weight of the amount of Formula (Id). In certain embodiments, the catalyst is Pd/C and the amount of Pd/C is between about 0.5% and 20%, between about 1% and 20%, between about 5% and 15%, or between about 8% and 12% by weight of the amount of Formula (Id). In one embodiment, the amount of catalyst is about 10% by weight of the amount of Formula (Id). In one embodiment, the catalyst is Pd/C and the amount of Pd/C is at least about 0.1%, at least about 0.5%, at least about 1%, at least about 3%, at least about 5%, at least about 8%, at least about 10%, at least about 12%, at least about 15%, or at least about 20% by weight of the amount of Formula (Id). 27 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [115] Non-limiting examples of aqueous acids include, but are not limited to, perchloric acid, hydrochloric acid, hydrobromic acid, acetic acid, sulfuric acid, citric acid, nitric acid, and phosphoric acid, or a mixture thereof. In one embodiment, the aqueous acid comprises perchloric acid. In one embodiment, the aqueous acid comprises hydrochloric acid. In one embodiment, the aqueous acid comprises hydrobromic acid. In one embodiment, the aqueous acid comprises acetic acid. In one embodiment, the aqueous acid comprises sulfuric acid. In one embodiment, the aqueous acid comprises citric acid. In one embodiment, the aqueous acid comprises phosphoric acid. [116] In one embodiment, the aqueous acid is a mixture of two aqueous acids comprising (i) a first aqueous acid selected from perchloric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, and nitric acid and (ii) a second aqueous acid selected from acetic acid, phosphoric acid, and citric acid. In one embodiment, the ratio of the first aqueous acid to the second aqueous acid is about 1:30, about 1:25, about 1:20, about 1:15, about 1:10, about 1:5, or about 1:1. [117] In one embodiment, the first aqueous acid is selected from perchloric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, and nitric acid and the second aqueous acid is acetic acid. In one embodiment, the aqueous acid is a mixture of sulfuric acid and acetic acid. In one embodiment, the ratio of sulfuric acid to acetic acid is between about 1:25 to 1:15. In one embodiment, the ratio of sulfuric acid to acetic acid is about 1:20. [118] In certain embodiments, the hydrogenation of step (b.2) is conducted at room temperature for at about least 12 hours, at least about 24 hours, at least about 36 hours, at least about 48 hours, or more. [119] In certain embodiments, the compound of Formula (Ic) is filtered to remove catalyst and used directly in step (c.1) without further purification. Step (c.1) [120] In certain embodiments, the oxidation of step (c.1) is conducted in the presence of an iron(III) salt, including, but not limited to iron(III) nitrate, iron(III) sulfate, iron(III) tartrate, iron(III) acetate, iron(III) citrate, iron(III) phosphate, iron(III) perchlorate, and an iron(III) halide. In one embodiment, the iron(III) salt is iron(III) chloride. In certain embodiments, the iron(III) salt is an hydrate, for example iron(III) perchlorate hydrate, iron(III) nitrate hydrate, or iron(III) chloride 6-hydrate. In one embodiment, the iron(III) salt hydrate is iron(III) chloride 6-hydrate. Alternative regents for the oxidation of step (c.1) include, but are not limited to, ceric ammonium nitrate (CAN), Jones reagent, chromium trioxide, and sodium dichromate. In 28 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 certain embodiments, the oxidation is in the presence of oxygen gas. In one embodiment, the oxygen gas is pure. In one embodiment, the oxygen gas is diluted, for example, in water. In one embodiment, the oxygen gas is diluted, for example, in N2. In one embodiment, the oxygen gas is less than about 10%, less than about 5%, or less than about 1% in N ₂ . In one embodiment, the oxygen gas is about 5% in N2. [121] In certain embodiments, the oxidation of step (c.1) is a biphasic oxidation. In one embodiment, the compound of Formula (Ic) is dissolved in organic solvent(s) and water is added. In one embodiment, the compound of Formula (Ic) from either step (b.1) or (b.2) is filtered to remove catalyst and is carried forward in step (c.1) where water is added for the oxidation. [122] In one embodiment, the organic solvent is one or more polar aprotic solvents, for example, ethyl acetate, isopropyl acetate, isopropyl alcohol, ethyl alcohol, or methyl cyclopentyl ether. In one embodiment, the organic solvent is a mixture of isopropyl acetate and isopropyl alcohol. In one embodiment, the organic solvent is methyl cyclopentyl ether (CPME). [123] In certain embodiments, the oxidation of step (c.1) is conducted in the organic solvent/water mixture at a concentration of the iron(III) salt of at least about 1.0 molar, at least about 1.5 molar, at least about 2.0 molar, at least about 2.5 molar, at least about 3.0 molar, at least about 3.5 molar, at least about 4.0 molar, or more. [124] In certain embodiments, the oxidation of step (c.1) is conducted for at least about 15 minutes, 30 minutes, 1 hour, 2 hours, 4 hours, 5 hours, or more. In one embodiment, the oxidation of step (c.1) is conducted for at least about 1 hour. In one embodiment, the oxidation of step (c.1) is conducted for at least about 2 hours. [125] Formula (I) can be isolated and purified by any method known to a person of skill in the art, including, but not limited to column chromatography, crystallization, trituration, and distillation. In certain embodiments the benzoquinone of Formula (I) is further purified by crystallization in a solvent/anti-solvent system, for example in an alcohol/water system. In one embodiment, the solvent is an alcohol, including, but not limited to, methanol, ethanol, n- propanol, isopropanol, and n-butanol. In one embodiment, the anti-solvent is water. In one embodiment, the benzoquinone of Formula (I) is further purified by crystallization in an isopropanol/water system. Purification via crystallization of a certain benzoquinone, 2,3,5- trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione, has been described in WO 2020/081879. 29 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [126] Additional examples of solvents for the solvent/anti-solvent system include other polar organic solvents, such as a C ₃ -C ₇ ester, for example, ethyl acetate; a C ₁ -C ₂ chlorocarbon, such as dichloromethane; a C3-C7 ketone, such as acetone; or DMSO. [127] In one embodiment, Formula (I) is purified via trituration wherein an anti-solvent is added to a solvent-based solution of Formula (I), for example wherein water is added to an alcohol. In one embodiment, the benzoquinone of Formula (I) is further purified by trituration in an isopropanol/water system. [128] In one embodiment, the oxidation of step (c.1) affords Formula (I) that is greater than about 85% pure, greater than about 90% pure, greater than about 95%, greater than about 98%, greater than about 99% pure, or about 100% pure. In one embodiment, the oxidation of step (c.1) affords Formula (I) wherein Formula (I) is greater than 95% pure. [129] In certain embodiments, the process for synthesizing the benzoquinone of Formula (I) comprises the steps of step (b.1) to afford Formula (Ic) and step (c.1) to afford Formula (I) wherein the intermediate of Formula (Ic) is isolated, but not purified, and used directly in step (c.1). [130] In certain embodiments, the process for synthesizing the benzoquinone of Formula (I) comprises the steps of step (b.2) to afford Formula (Ic) and step (c.1) to afford Formula (I) wherein the intermediate of Formula (Ic) is isolated, but not purified, and used directly in step (c.1). [131] In certain embodiments, the process for synthesizing the benzoquinone of Formula (I) comprises the steps of step (a.1) to afford Formula (Ia) and/or Formula (Ib); step (b.1) to afford Formula (Ic); and, step (c.1) to afford Formula (I) wherein the intermediates of Formula (Ia) and/or Formula (Ib) and Formula (Ic) are isolated, but not purified, and are used directly each subsequent step. In this embodiment, the only purification in the synthesis is the purification of Formula (I) after step (c.1). [132] In certain embodiments, the process for synthesizing the benzoquinone of Formula (I) comprises the steps of step (a.2) to afford Formula (Id); step (b.2) to afford Formula (Ic); and, step (c.1) to afford Formula (I) wherein the intermediates of Formula (Id) and Formula (Ic) are isolated, but not purified, and are used directly each subsequent step. In this embodiment, the only purification in the synthesis is the purification of Formula (I) after step (c.1). 30 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 Flow Chemistry Conditions [133] In another aspect, a benzoquinone of Formula (I) is synthesized using flow chemistry conditions. In some or any embodiments described herein, the steps of (a.1), (b.1), and/or (c.1) are conducted using flow chemistry. In one embodiment, the process for synthesizing a benzoquinone of Formula (I) comprises the steps of (b.1) and (c.1) wherein both steps are conducted using flow chemistry as described herein. In one embodiment, the process for synthesizing a benzoquinone of Formula (I) comprises the steps of (a.1), (b.1) and (c.1) wherein the steps are conducted using flow chemistry as described herein. In some or any embodiments, the process for synthesizing an alkyl-substituted hydroquinone of Formula (Ic) comprises the step of (b.1) using flow chemistry. In some or any embodiments, the process for synthesizing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl- substituted quinone of Formula (Ib) comprises the step of (a.1) using flow chemistry. step (a.1) [134] In one embodiment, the condensation of step (a.1) using flow chemistry is conducted as shown in FIG.3. [135] In one embodiment, reactor vessel 100 is charged with water. In one embodiment, reactor vessel 110 is charged a C2-C8ether; an acid catalyst, for example, a sulfonic acid; and, a trialkylhydroquinone of Formula (Ie). In one embodiment, reactor vessel 110 is charged with cyclopentyl methyl ether (CPME), para-toluenesulfonic acid monohydrate, and a trialkylhydroquinone of Formula (Ie). In one embodiment, the reactor vessel 110 is stirred to afford a clear solution at a temperature between about 20 ° and 30 °C. [136] In one embodiment, reactor vessel 120 is charged with a C ₂ -C ₈ ether, including, but not limited to dimethyl ether, methyl-t-butyl ether (MTBE), and cyclopentyl methyl ether (CPME) and an aldehyde of Formula (If). In one embodiment, reactor vessel 120 is charged with CPME and an aldehyde of Formula (If). In one embodiment, the mixture is stirred at a temperature between about 20 ° and 30 °C to afford a clear solution. [137] In one embodiment, reactor vessel 130 is charged with an aqueous solution of NaHCO ₃ and the reactor vessel is stirred at a temperature between about 15 ° and 25 °C to afford a clear solution. [138] In a preferred embodiment, the C2-C8ether in both reactor vessel 110 and reactor vessel 120 is cyclopentyl methyl ether (CPME). 31 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [139] As shown in FIG.3, once each reactor vessel is charged, reactor tubing 111, 121, 113, 114, 124, 115, 125, 116, and 126 are filled with the C ₂ -C ₈ ether, for example CPME, and the back pressure regulator 200 is set to a pressure in the range of about 100 – 200 psi, preferably about 150 psi. The high temperature oven 210 is set to a temperature between about 160 °C and 180 °C, preferably about 160 °C. [140] First, pump 112 pumps the solution in reactor vessel 110 from vessel 110 to static mixer 220 via reactor tubing 111, 113, and 114. Simultaneously, pump 121 pumps the solution in reactor vessel 120 from vessel 120 to static mixture 220 via reactor tubing 121, 113, and 114. Reactor tubing 113 is connected to both pump 112 and pump 122 and reactor tubing 113 has convergence point 123 that is further connected to reactor tubing 114, which is connected to static mixer 220. When the solution from reactor vessel 110 flows through reactor tubing 113 and reaches convergence point 123, the solution flows to reactor tubing 114. When the solution from reactor vessel 120 flows through reactor tubing 113 and reaches convergence point 123, the solution flows to reactor tubing 114 to static mixer 220. In static mixer 220, the solution comprising an aldehyde of Formula (If) from reactor vessel 120 and the solution comprising a trialkylhydroquinone of Formula (Ie) from reactor vessel 110 mix. [141] From static mixer 220, a solution comprising an aldehyde of Formula (If) and a trialkylhydroquinone of Formula (Ie) is pumped to the preheater 230 via reactor tubing 124. From preheater 230, the solution is pumped to high temperature oven 210 via reactor tubing 115 where the trialkylhydroquinone of Formula (Ie) and the aldehyde of Formula (If) react to form an alkenyl-substituted hydroquinone of Formula (Ia) and/or an alkenyl-substituted quinone of Formula (Ib). In one embodiment, the condensation of trialkylhydroquinone of Formula (Ie) and the aldehyde of Formula (If) in high temperature oven 210 is conducted for at least about 2 hours, at least about 90 minutes, at least 70 minutes, about at least 1 hour, at least about 45 minutes, at least about 30 minutes, at least about 20 minutes, or at least about 15 minutes. In one embodiment, the condensation reaction in high temperature oven 210 is conducted for about 70 minutes at a temperature of about 160 °C. [142] Once the reaction is complete, the solution of alkenyl-substituted hydroquinone of Formula (Ia) and/or an alkenyl-substituted quinone of Formula (Ib) is pumped from oven 210 to post-cooling chamber 240 via reactor tubing 125 and then from the post-cooling chamber 240 to vessel 250. The solution moves from chamber 240 to vessel 250 via reactor tubing 116, which transports the solution to regulator 200 and from regulator 200 to vessel 250. The 32 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 solution moves from regulator 200 to vessel 250 via reactor tubing 126. Reactor tubing 126 has convergence point 127 that is further connected to reactor tubing 134. [143] Next, pump 133 is set to an appropriate flow rate to pump the aqueous solution in reactor vessel 130. The solution first moves from reactor vessel 130 to pump 133 via reactor tubing 131 and is then pumped to vessel 250. The solution flows from reactor tubing 134 and at convergence point 127, flows through reactor tubing 126 to vessel 250 to quench the condensation reaction. Once the reaction is complete, the resulting aqueous layer is moved to the aqueous phase waste vessel 280 via reactor tubing 117. Reactor tubing 117 contains convergence points 135 and 136. Once the aqueous layer is removed, an organic phase comprising alkenyl-substituted hydroquinone of Formula (Ia) and/or an alkenyl-substituted quinone of Formula (Ib) remains in vessel 250. [144] Pump 102 is next set to an appropriate flow rate to pump the water from reactor vessel 100. Water moves from reactor vessel 100 to pump 102 via reactor tubing 101 and from pump 102 to vessel 260 via reactor tubing 103. Reactor tubing 103 has a convergence point 104 and once water reaches convergence point 104, the water flows to reactor tubing 115. Reactor tubing 115 has convergence point 129 and once water reaches convergence point 129, water flows to reactor tube 128 and from reactor tube 128 to vessel 260. [145] In one embodiment, the organic phase in vessel 250 is first transported to vessel 260 via reactor tubing 128 and once the organic phase is moved to vessel 260, water is added via reactor tubing 101, 103, 115, and 128 (via convergence point 129) to vessel 260. In another embodiment, the organic phase in vessel 250 is transported to vessel 260 via reactor tubing 128 while water is added simultaneously to vessel 260 via reactor tubing 101, 103, 115, and 129. [146] Once vessel 260 contains both the organic phase from vessel 250 and water from reactor vessel 100, the organic phase is washed and the aqueous phase is separated from the organic phase. The aqueous phase is removed to aqueous phase waste vessel 280. The aqueous phase flows from vessel 260 to reactor tubing 105 and once the aqueous phase reaches convergence point 135, the aqueous phase flows through reactor tubing 117 and into waste vessel 280. [147] In a final step, water moves from reactor tubing 103 to reactor tubing 107 via a second convergence point 106. Water then flows from tubing 107 to vessel 270. [148] In one embodiment, the organic phase in vessel 260 is first transported to vessel 270 via reactor tubing 107 and once the organic phase is moved to vessel 270, water is added via reactor tubing 101, 103, and 107. In another embodiment, the organic phase in vessel 260 is 33 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 transported to vessel 270 via reactor tubing 107 while water is added simultaneously to vessel 270 via reactor tubing 101, 103, and 107. [149] Once vessel 270 contains both the organic phase from vessel 260 and water from reactor vessel 100, the organic phase is washed and the aqueous phase is separated from the organic phase. The aqueous phase is removed to aqueous phase waste vessel 280. The aqueous phase flows from vessel 270 to reactor tubing 108 and once the aqueous phase reaches convergence point 136, the aqueous phase flows to reactor tubing 117 and into waste vessel 280. The organic phase from vessel 270 is then transported to the organic phase holding vessel 290 via reactor tubing 109. Organic phase holding vessel 290 holds the solution of alkenyl-substituted hydroquinone of Formula (Ia) and/or an alkenyl-substituted quinone of Formula (Ib) in the C ₂ - C8ether for step (b.1). [150] In one embodiment, the aqueous phase waste vessel is purged with N2 via reactor tubing 281. In one embodiment, reactor vessel 100 is purged with N2 via reactor tubing 141, reactor vessel 110 is purged with N2 via reactor tubing 142, reactor vessel 120 is purged with N2 via reactor tubing 143, and reactor vessel 130 is purged with N2 via reactor tubing 144. [151] In one embodiment, the flow rate of pump 102 is set to a rate of about 2.5 mL/min to about 3.5 mL/min. In one embodiment, the flow rate of pump 102 is set to a rate of about 2.85 mL/min to about 3.15 mL/min, and is preferably set to a rate of about 3.0 mL/min. [152] In one embodiment, the flow rate of pump 112 is set to a rate of about 3.5 mL/min to about 4.0 mL/min. In one embodiment, the flow rate of pump 112 is set to a rate of about 3.5 mL/min to about 3.7 mL/min, and is preferably set to a rate of about 3.66 mL/min. [153] In one embodiment, the flow rate of pump 122 is set to a rate of about 1.5 mL/min to about 2.0 mL/min. In one embodiment, the flow rate of pump 122 is set to a rate of about 1.71 mL/min to about 1.89 mL/min, and is preferably set to a rate of about 1.8 mL/min. [154] In one embodiment, the flow rate of pump 133 is set to a rate of about 1.0 mL/min to about 1.5 mL/min. In one embodiment, the flow rate of pump 133 is set to a rate of about 1.24 mL/min to about 1.37 mL/min, and is preferably set to a rate of about 1.3 mL/min. [155] In one embodiment, the flow rate of pump 102 is set to a rate of about 2.85 mL/min to about 3.15 mL/min; the flow rate of pump 112 is set to a rate of about 3.5 mL/min to about 3.7 mL/min; the flow rate of pump 122 is set to a rate of about 1.71 mL/min to about 1.89 mL/min; and, the flow rate of pump 133 is set to a rate of about 1.24 mL/min to about 1.37 mL/min. [156] In one embodiment, the flow rate of pump 102 is set to a rate of about 2.85 mL/min to about 3.15 mL/min; the flow rate of pump 112 is set to a rate of about 3.5 mL/min to about 3.7 34 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 mL/min; the flow rate of pump 122 is set to a rate of about 1.71 mL/min to about 1.89 mL/min; the flow rate of pump 133 is set to a rate of about 1.24 mL/min to about 1.37 mL/min; and, the oven temperature of 210 is set to about 160 °C. [157] In one embodiment, the condensation of step (a.1) using the flow chemistry described herein is the condensation of 2,3,5-trimethylbenzene-1,4-diol and nonanal to afford (E)-2,3,5- trimethyl-6-(non-1-en-1-yl)benzene-1,4-diol and/or (E)-2,3,5-trimethyl-6-(non-1-en-1- yl)cyclohexa-2,5-diene-1,4-dione. step (b.1) [158] In one embodiment, the reduction of step (b.1) using flow chemistry is conducted as shown in FIG.4 using hydrogenator system 300. [159] In one embodiment, reactor vessel 400 is charged with the solution of alkenyl- substituted hydroquinone of Formula (Ia) and/or alkenyl-substituted quinone of Formula (Ib) in the C2-C8ether from step (a.1). The tubular reactor 301 is next charged with the catalyst. In one embodiment, the catalyst is selected from Pd/C, Pt/C, Pd(OH)2/C, PtO2, Pd(OH)2/Al2O3, Raney Nickel, Ru/CaCO3, and Pd/CaCO3. In an alternative embodiment, the catalyst is Pd/Al ₂ O ₃ . [160] In one embodiment, the catalyst is Pd(OH)2/Al2O3. In a further embodiment, the catalyst is Pd(OH) ₂ /Al ₂ O ₃ and the amount of Pd(OH) ₂ /Al ₂ O ₃ is between about 0.1% and 20% by weight of the amount of Formula (Ia) and/or Formula (Ib). In certain embodiments, the catalyst is Pd(OH) ₂ /Al ₂ O ₃ and the amount of Pd(OH) ₂ /Al ₂ O ₃ is between about 0.5% and 20%, between about 1% and 20%, between about 5% and 15%, or between about 8% and 12% by weight of the amount of Formula (Ia) and/or Formula (Ib). In one embodiment, the amount of Pd(OH)2/Al2O3 is about 4% by weight of the amount of Formula (Ia) and/or Formula (Ib). [161] As shown in FIG.4, tubular reactor 301 is connected to vessel 410 containing hydrogen via reactor tubing 411 and 412. Tubular reactor 301 is filled with hydrogen by setting an appropriate flow rate using flow meter 302. The hydrogen flows from vessel 410 to the flow meter 302 via reactor tubing 411 and from flow meter 302 to tubular reactor 301 via reactor tubing 412. In one embodiment, the flow rate of hydrogen is between about 20 and 40 mL/min, preferably between about 25 and 35 mL/min. In one embodiment, the flow rate is about 30 mL/min. The temperature of tubular reactor 301 is also set to an appropriate temperature. In one embodiment, the temperature is in the range of about 15 – 40 °C. In one embodiment, the temperature is about 20 - 25 °C. 35 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [162] As shown in FIG. 4, step (b.1) hydrogenation is conducted with an upflow reactor. In an alternative embodiment, step (b.1) is conducted with a down flow reactor. [163] Next, back-pressure regulator 304 is set to an appropriate pressure, for example, 2.0- 2.5 mPa. In one embodiment, back-pressure regulator 304 is set to 2.2 mPa. Pump 303 is set to an appropriate flow rate and the solution of alkenyl-substituted hydroquinone of Formula (Ia) and/or alkenyl-substituted quinone of Formula (Ib) in the C ₂ -C ₈ ether from reactor vessel 400 flow from vessel 400 through reactor tubing 401 to pump 303, where it next flows from pump 303 to tubular reactor 301 via reactor tubing 402. In tubular reactor 301, the solution of alkenyl- substituted hydroquinone of Formula (Ia) and/or alkenyl-substituted quinone of Formula (Ib) in the C ₂ -C ₈ ether is reduced in the presence of the catalyst to afford an alkyl-substituted hydroquinone of Formula (Ic). [164] Once the reaction is complete, as monitored by periodically removing a sample from tubular reactor 301, the solution of alkyl-substituted hydroquinone of Formula (Ic) in the C2- C8ether is allowed to flow from tubular reactor 301 to collection vessel 420 by first flowing from tubular reactor 301 to back pressure regulator 304 via reactor tubing 403 and from back pressure regulator 304 to collection vessel 420 via reactor tubing 404 and 405. Collection vessel 420 is also vented via reactor tubing 406. [165] In one embodiment, tubular reactor 301 is a fixed-bed reactor. In one embodiment, tubular reactor 301 is a 5 mL fixed-bed reactor. [166] In one embodiment, the reduction of step (b.1) using the flow chemistry described herein is the reduction of (E)-2,3,5-trimethyl-6-(non-1-en-1-yl)benzene-1,4-diol and/or (E)- 2,3,5-trimethyl-6-(non-1-en-1-yl)cyclohexa-2,5-diene-1,4-dio ne to afford 2,3,5-trimethyl-6- nonylbenzene-1,4-diol. step (c.1) [167] In one embodiment, the oxidation of step (c.1) using flow chemistry is conducted as shown in FIG.5. [168] In one embodiment, reactor vessel 600 is charged with the solution of alkyl-substituted hydroquinone of Formula (Ic) in the C2-C8ether from step (b.1). In one embodiment, reactor vessel 600 is purged with N ₂ via reactor tubing 601 and reactor tubing 602, 604, 605, 607, and 621 are filled with the same kind of C2-C8ether used in step (b.1). Back-pressure regulator 620 is adjusted to a pressure of about 700 to 800 psi, preferably 750 psi and the oven temperature of system 500 is set to about 80 to 100 °C, preferably 90 °C. 36 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [169] Reactor vessel 610 is charged with a mixture of diluted O ₂ and the flow rate of the diluted O ₂ is set via mass flow 612. In one embodiment, the diluted O ₂ is about 5% O ₂ in N ₂ . In one embodiment, the flow rate of the diluted O2 is about 200-250 mL/min, preferably 225 mL/min. The flow rate of the solution of alkyl-substituted hydroquinone of Formula (Ic) in the C2-C8ether from step (b.1) is set using pump 603. In one embodiment, pump 603 is set to a flow rate of about 1.75 mL/min to 2.5 mL/min. In one embodiment, pump 603 is set to a flow rate of about 1.88 mL/min to 2.28 mL/min, preferably 2.08 mL/min. [170] The solution of alkyl-substituted hydroquinone of Formula (Ic) in the C ₂ -C ₈ ether flows from reactor vessel 600 to pump 603 through reactor vessel 602 and from pump 603 to pre- heating tubing 501 through reactor tubing 604. From pre-heating tubing 501, the solution flows to reaction tubing 502 via reactor tubing 605. Reactor tubing 605 has convergence point 606 that intersects with reactor tubing 613. [171] Once reaction tubing 502 is filled with the solution of alkyl-substituted hydroquinone of Formula (Ic) in the C2-C8ether, the diluted O2 flows from reactor vessel 610 to mass flow 612 via reactor tubing 611 and from mass flow 612 to reactor tubing 613. Reactor tubing 613 intersects with reactor tubing 605 via convergence point 606 and once the diluted O2 reaches convergence point 606, it travels to reaction tubing 502 via reactor tubing 605 where the diluted O2 is mixed with alkyl-substituted hydroquinone of Formula (Ic) for oxidation to form benzoquinone of Formula (I). Once complete, the solution of the benzoquinone of Formula (I) in C2-C8ether flows from reaction tubing 502 to collection vessel 630 by flowing through reactor tubing 607 to back-pressure regulator 620 and from regulator 620 to vessel 630 via reactor tubing 621. Reactor tubing 622 allows for collection vessel 630 to be vented. [172] In one embodiment, pre-heating tube 501 is a stainless steel tube wherein the internal diameter is between about 1/16 ^th and 1/8 ^th of an inch and is between about 1 and 3 meters long. In one embodiment, pre-heating tube 501 is a stainless steel tube wherein the internal diameter is about 1/16 ^th of an inch and is about 2 meters long. [173] In one embodiment, reaction tubing 502 is a stainless steel tube wherein the internal diameter is between about 1/16 ^th and 1/8 ^th of an inch, preferably 1/8 ^th of an inch. [174] The solution of the benzoquinone of Formula (I) in C2-C8ether from collection vessel 630 is then concentrated under reduced pressure and the solvent is exchanged for MeOH. This process of concentration and solvent exchange is repeated at least once, twice, or three times. In one embodiment, the process is repeated twice. The solution of benzoquinone of Formula (I) in MeOH is next concentrated under reduced pressure and stirred at about 60 to 65 ° for 37 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 about 2-3 hours. Following the stirring at about 60 to 65 °, the temperature is adjusted to about 25-35 °C over the course of about 2-5 hours. A seed of benzoquinone of Formula (I) in C ₂ - C8ether is added and the mixture is again stirred for about 25-35 °C over the course of about 3-5 hours. The temperature of the mixture is then adjusted to about -5 to 5 °C over the course of about 3-5 hours and then stirred at a temperature of about -5 to 5 °C for about 5- 8 hours. Following filtration of the mixture, the wet cake is washed with MeOH and dried at 25-35 °C under reduced pressure to afford the crude benzoquinone of Formula (I). [175] For the crystallization, acetone is added to crude benzoquinone of Formula (I) and the mixture is stirred at about 20-30 °C, preferably about 25 °C, for about 0.5 -5 hours. In one embodiment, the solution is stirred for about 2 hours. The suspension is then filtered and the temperature of the mother liquor is adjusted to about 20-30 °C, preferably about 25 °C and stirred for about 0.5 to 1.5 hours, preferably 1 hour. Purified water is added dropwise to the solution over the course of about 0.5 to 2 hours, preferably 0.5 hours, before a seed crystal of benzoquinone of Formula (I) is added and the suspension is stirred for about 1 to 3 hours, preferably 12 hours. Additional purified water is again added to the suspension dropwise over the course of about 6 – 10 hours, preferably 8 hours and the suspension is stirred for an additional 6 to 20 hours, preferably 7 hours to afford the benzoquinone of Formula (I). [176] The benzoquinone of Formula (I) is the wet-milled to D90 < 100 µm, filtered, and washed with a solution of acetone and water, and dried to afford pure benzoquinone of Formula (I). [177] In one embodiment, the oxidation of step (c.1) using the flow chemistry described herein is the oxidation of 2,3,5-trimethyl-6-nonylbenzene-1,4-diol to afford 2,3,5-trimethyl-6- nonylcyclohexa-2,5-diene-1,4-dione. [178] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (a.1) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof and an aldehyde of Formula (If) to afford an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib): ; 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 (b.1) reducing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib) to afford an alkyl-substituted hydroquinone of Formula (Ic): (c.1) to afford the benzoquinone of or a solvate, and/or hydrate thereof: ; wherein R ¹ , R ² , and R ³ and R ⁴ is C _4-10 alkyl. [179] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof or an alkyl-substituted hydroquinone of Formula (Ic) or a salt, a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (a.1) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof and an aldehyde of Formula (If) to afford an alkenyl-substituted hydroquinone of Formula (Ia) or a salt thereof and/or an alkenyl-substituted quinone of Formula (Ib): thereof and/or an alkenyl-substituted quinone of Formula (Ib) to afford an alkyl-substituted hydroquinone of Formula (Ic) or a salt thereof: ; wherein R ¹ , R ² , is C4-10alkyl. 39 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [180] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (b.1) reducing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib) to afford an alkyl-substituted hydroquinone of Formula (Ic) or salt thereof: (c.1) or salt thereof to afford the or a solvate, and/or hydrate thereof: ; wherein R ¹ , R ² , and R ³ and R ⁴ is C4-10 alkyl. [181] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (a.2) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof with an aldehyde of Formula (If) to afford an acetal of Formula (Id) or salt thereof: ; (b.2) the alkyl- substituted hydroquinone of Formula (Ic) or salt thereof: 40 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 (c.1) (Ic) or salt thereof to afford the or a solvate, and/or hydrate thereof: ; wherein R ¹ , R ² , and R ³ and R ⁴ is C4-10alkyl. [182] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof or an alkyl-substituted hydroquinone of Formula (Ic) or salt thereof comprises the steps of: (a.2) condensing a trialkylhydroquinone of Formula (Ie) or salt thereof with an aldehyde of Formula (If) to afford an acetal of Formula (Id) or salt thereof: (b.2) the alkyl- substituted hydroquinone of Formula (Ic) or salt thereof: . 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [183] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (b.2) hydrogenating an acetal of Formula (Id) or salt thereof to afford the alkyl- substituted hydroquinone of Formula (Ic) or salt thereof: ; and (c.1) (Ic) or salt thereof to afford the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof: ; wherein R ¹ , R ² , and R ^{3 4} and R is C _4-10 alkyl. [184] In some or any embodiments, the process for synthesizing the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof comprises the steps of: (b.1) reducing an alkenyl-substituted hydroquinone of Formula (Ia) or salt thereof and/or an alkenyl-substituted quinone of Formula (Ib) to afford an alkyl-substituted hydroquinone of Formula (Ic) or salt thereof under catalytic hydrogenation conditions in the presence of Pd/C: or (b.2) the alkyl- substituted hydroquinone of Formula (Ic) or salt thereof in the presence of Pd/C: 42 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 ; and (c.1) (Ic) or salt thereof to afford the benzoquinone of Formula (I) or a stereoisomer, mixture of stereoisomers, solvate, and/or hydrate thereof in the presence of Fe3Cl • 6 H2O: ; wherein R ¹ , R ² , and R ⁴ is C4-10 alkyl. [185] In one embodiment, the compound of Formula (I) is 2,3,5-trimethyl-6- nonylcyclohexa-2,5-diene-1,4-dione or a solvate and/or hydrate thereof and the process for synthesizing 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4-dione comprises the steps of: (b.1) reducing 2,3,5-trimethyl-6-(non-1-en-1-yl)benzene-1,4-diol and/or an 2,3,5- trimethyl-6-(non-1-en-1-yl)cyclohexa-2,5-diene-1,4-dione to afford 2,3,5-trimethyl-6- nonylbenzene-1,4-diol: or (b.2) ol to afford 2,3,5-trimethyl-6-nonylbenzene-1,4-diol: (c.1) 6- nonylcyclohexa-2,5-diene-1,4-dione or a solvate and/or hydrate thereof: 43 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 . [186] In one process 4H- benzo[d][1,3]dioxin-6-ol or for synthesizing 2,3,5-trimethyl-6-nonylcyclohexa-2,5-diene-1,4- dione further comprises an (a.1) step before the (b.1) step: (a.1) condensing 2,3,5-trimethylbenzene-1,4-diol and nonanal to afford 2,3,5- trimethyl-6-(non-1-en-1-yl)benzene-1,4-diol and/or an 2,3,5-trimethyl-6-(non-1-en-1- yl)cyclohexa-2,5-diene-1,4-dione: or further (a.2) condensing 2,3,5-trimethylbenzene-1,4-diol and nonanal to afford 5,7,8- trimethyl-2,4-dioctyl-4H-benzo[d][1,3]dioxin-6-ol: . [187] In some or any 2,3,5-trimethyl-6- nonylbenzene-1,4-diol or a pharmaceutically acceptable salt, solvate, and/or hydrate thereof comprises the steps of: (b.1) reducing 2,3,5-trimethyl-6-(non-1-en-1-yl)benzene-1,4-diol and/or an 2,3,5- trimethyl-6-(non-1-en-1-yl)cyclohexa-2,5-diene-1,4-dione to afford 2,3,5-trimethyl-6- nonylbenzene-1,4-diol: 44 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 or (b.2) 6-ol to afford 2,3,5- . [188] In 6-(non-1-en- 1-yl)benzene-1,4-diol and/or 2,3,5-trimethyl-6-(non-1-en-1-yl)cyclohexa-2,5-diene-1,4-dio ne comprises an (a.1) step: (a.1) condensing trimethyl-hydroquinone and nonanal to afford 2,3,5-trimethyl-6- (non-1-en-1-yl)benzene-1,4-diol and/or 2,3,5-trimethyl-6-(non-1-en-1-yl)cyclohexa-2,5- diene-1,4-dione: . [189] 2,4-dioctyl- 4H-benzo[d][1,3]dioxin-6-ol comprises an (a.2) step: (a.2) condensing trimethyl-hydroquinone with nonanal to afford 5,7,8-trimethyl-2,4- dioctyl-4H-benzo[d][1,3]dioxin-6-ol: . [190] In (Ib), and Formula (Id) or a salt thereof are provided: 45 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 or a wherein R ¹ , R ² , and R ³ are independently selected from C1-4alkyl; and R ⁴ is C4-10alkyl. [191] In certain embodiments of Formula (I), Formula (Ia), Formula (Ib), Formula (Ic), or Formula (Id), R ¹ , R ² , and R ³ are each independently a straight C1-4alkyl chain and R ⁴ is a straight C _4-10 alkyl chain. In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C1-2alkyl and R ⁴ is C4-7alkyl. In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C1-2alkyl and R ⁴ is C7-10alkyl. In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C _2- 4alkyl and R ⁴ is C4-7alkyl. In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C _2-4 alkyl and R ⁴ is C _7-10 alkyl. In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C3-4alkyl and R ⁴ is C4-7alkyl. In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are each independently selected from C3- 4alkyl and R ⁴ is C7-10alkyl. [192] In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are independently selected from C1-2alkyl, C2-4alkyl, and C3-4alkyl. In certain embodiments of Formula (Ia), Formula (Ib), or Formula (Id), R ¹ , R ² , and R ³ are each methyl. [193] In certain embodiments, the compound of Formula (Id) is of the formula . [194] In certain embodiments, the (Id) is of the formula 46 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 . [195] In certain embodiments, the (Id) is of the formula . [196] In certain is of the formula: , , , . 47 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [197] In certain embodiments, the compound of Formula (Id) is of the formula: , , [198] . [199] In certain embodiments, (Id) is of the formula: . 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 Synthetic Reaction Parameters [200] The terms “solvent,” “inert organic solvent,” and “inert solvent” embrace a solvent that is inert under the conditions of the reaction being described in conjunction therewith. Solvents employed in synthesis of the compounds disclosed herein include, in some embodiments, methanol (“MeOH”), acetone, water, acetonitrile, 1,4-dioxane, dimethylformamide (“DMF”), benzene, toluene, xylene, tetrahydrofuran (“THF”), chloroform, methylene chloride (or dichloromethane, (“DCM”)), diethyl ether, pyridine and the like, as well as mixtures thereof. Unless specified to the contrary, the solvents used in the reactions disclosed herein are inert organic solvents. [201] The term “eq” means an equivalent quantity of one reagent with respect to another reagent. [202] Temperature in the examples below refers to bath temperature. [203] While the Examples illustrate some of the diverse methods available for use in assembling the compounds herein, they are not intended to define the scope of reactions or reaction sequences that are useful in preparing the compounds herein. EXAMPLES [204] The disclosure will be further understood by the following non-limiting examples. General Method [205] Most of chemicals including TMHQ, 1-nonanal, CPME, FeCl ₃ ∙6H ₂ O were purchased from Shanghai Titan Scientific Co., Ltd. [206] ¹ H NMR spectra were recorded on Bruker AVⅢ 400. [207] LCMS measurement was run on Agilent 1200 HPLC/6100 SQ System using the follow conditions: Mobile Phase: A: Water (0.05%TFA) B: ACN (0.05%TFA) Gradient: 5% increase to 95% B within 1.3 min, 95% B for 1.7min Flow Rate: 2mL/min Column: XBridge C18, 4.6*50mm, 3.5um Column Temperature: 45 ^o C Detection: UV (214, 254 nm) and MS (ESI, Pos mode,110 to 1100 amu) 49 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 Abbreviations ACN acetonitrile CPME cyclopentyl methyl ether [209] Compound 1-1 (TMHQ, 50.0 g, 0.33 mol) and p-TsOH∙H ₂ O (6.25 g, 0.033 mol) were dissolved in CPME (500 mL). The mixture was heated to 100 °C (inner temperature) and Compound 1-2 (56.0 g, 0.39 mol) was added in one portion. The reaction mixture was stirred at 100 °C under nitrogen and the reaction was monitored by LCMS. After stirring for 7 hours, LCMS indicated the desired Compound 1-3a as the major peak. Compound 1-3b was also detected as minor byproduct. The reaction mixture was cooled to room temperature and used in the next step directly. [210] Step 2: Synthesis of Compound 1-4 [211] To the reaction mixture of Step 1 was added 10% Pd/C (9.0 g, 10% weight). The reaction mixture was evacuated and then replaced with hydrogen. The reaction mixture was stirred under a fully filled hydrogen balloon and the reaction mixture was monitored. The hydrogen balloon was replaced when the pressure decreased. After stirring for 26 hours, the 50 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 LCMS indicated complete conversion of Compound 1-3a into Compound 1-4. The reaction mixture was filtered to remove Pd/C and used in the next step directly. [212] Step 3: Synthesis of Compound 1 [213] To the above reaction mixture was added a solution of FeCl3∙6H2O (177.5 g, 0.66 mol) in 200 mL of H ₂ O. The mixture was stirred at room temperature for 1 hour. LCMS indicated complete conversion of Compound 1-4 to Compound 1. The reaction was quenched with 500 mL of H ₂ O and the resulting two phases were partitioned. The organic phase was filtered to remove any possible suspended material and concentrated to approximately 60 mL. To the residue was added IPA (400 mL) in one portion, followed by addition of H ₂ O (100 mL) in a dropwise manner. After stirring at 25 °C for 2 hours, solid formation was observed. The mixture was cooled to 5 °C and further stirred for 2 hours at which point additional solid precipitated. The solid was collected by filtration and dried under vacuum to afford Compound 1 (48.77 g, 0.18 mol, 53.6% yield) as a bright yellow solid. [214] The purity was >95% according to ¹ HNMR and LCMS. LCMS: ESI-MS: m/z: 277 [M+H]+; RT=2.47 min.. ¹ H NMR (400 MHz, CDCl3) δ ppm, 2.44 (t, J = 8.0 Hz, 2H), 2.02- 2.01 (m, 9H), 1.35-1.26 (m, 14H), 0.87 (t, J = 6.2 Hz, 3H) ppm. [215] FIG.1 is the ¹ NMR spectrum of Compound 1 from Example 1. Example 2. Synthesis of Compound 1 via Benzodioxine intermediate Attorney Docket No.112738.01289 P1671-WO2 [216] Step 1: Synthesis of Compound 1-5 [217] Compound 1-1 (TMHQ, 4.5 g, 29.6 mmol), concentrated HCl (4.5 mL), iPrOAc (4.5 mL), and HOAc (40 mL) were mixed in the three-necked flask to form a thick slurry. The slurry was stirred by mechanical stirrer (900r/min) under nitrogen protection. Compound 1-2 (10.5 g, 73.9 mmol) in 13.5 mL of HOAc was added to the above mixture via syringe pump over the course of three hours, and after addition, the mixture was further stirred for 16 hours. LCMS monitoring indicated formation of the desired Compound 1-5 (LCMS also indicated the presence of TMHQ and TMQ). To the reaction was added iPrOAc (100 mL) to form a homogenous solution and the resulting solution was further stirred at 25 °C for 30 minutes. At this point the LCMS indicated almost complete conversion of the TMHQ. The peak corresponding to Compound 1-5 was detected as a major peak (1.32 min, 214 nm). The reaction mixture was used in Step 2 directly. [218] Step 2: Synthesis of Compound 1-4 [219] To the mixture from step 1 was added 1.1 g of 10% Pd/C (10% weight of the theoretical amount of Compound 1-5), and the mixture was stirred under hydrogen provided by a balloon. After stirring for 48 hours, Compound 1-5 was detected as the major peak via LCMS. The mixture was filtrated to remove Pd/C and the filtrate was washed with H2O (100 mL three times). The organic phase was concentrated to afford crude product (14 g). To 13 g of the crude material, was added HOAc (200 mL) and H2SO4 (10 mL). Most of the crude was dissolved, but not completely dissolved. To the mixture was added 10% Pd/C (1.1 g) and the mixture was stirred under hydrogen provided by a balloon for 16 hours. At this point, LCMS monitoring indicated full conversion of Compound 1-5 and Compound 1-4 was detected as the major product. The mixture was diluted with DCM (200 mL) and filtered to remove Pd/C. The resulting mixture was used in step 3 directly. [220] Step 3: Synthesis of Compound 1 [221] To the above solution in step 2 was added an aqueous solution of FeCl ₃ ∙6H ₂ O (10 g, 36.9 mmol) in water (50 mL). The mixture was stirred at 25 °C (room temperature) for 2 hours at which point LCMS monitoring indicated that Compound 1-4 was oxidized to Compound 1. After standing for 30 minutes, the mixture separated into two layers and the upper water layer was partitioned. The organic phase was concentrated to remove DCM and H ₂ O (100 mL) was added. The resulting mixture was extracted with petroleum ether (100 mL) three times and the 52 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 combined organic phases were washed with brine (100 mL). The petroleum ether was removed under reduced pressure to obtain crude material (12.3 g) that was crystallized with IPA (40 mL) and H2O (8 mL) as described in Step 3 of Example 1 to afford Compound 1 (4.3 g, overall yield of 57.0%) as a yellow solid. [222] LCMS showed minor impurities. ¹ HNMR indicated good purity. FIG. 2 is the ¹ NMR spectrum of Compound 1 from Example 2. Example 3. Synthesis of Compound 1 via Direct Condensation using Flow Chemistry [223] (Compound 1-2), and p-toluenesulfonic acid monohydrate (p-TsOH-H ₂ O) in cyclopentylmethyl ether (CPME) was heated to 160-180 °C to afford an E/Z mixture of Compound 1-3a and Compound 1-3b. After the reaction, the catalyst, p-TsOH, was removed by aqueous wash and the resulting solution was hydrogenated to afford intermediate Compound 1-4. In step 3, Compound 1-4 solution was oxidized by oxygen. The crude product, obtained by crystallization in methanol, was recrystallized in acetone-water to give pure Compound 1. The particle size was reduced to <100 ^m (D90) by wet-milling. Below are the descriptions of the operation for Steps 1 to 4. 53 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [224] Step 1 [225] Briefly, as shown in FIG. 3, a mixture of Compound 1-1 (TMHQ) with p-TsOH-H ₂ O (0.1 equiv) in CPME and a solution of Compound 1-2 (1-nonanal, 1.4 equiv) in CPME were mixed and continuously fed into a flow reactor at 160-180 °C with residence time about 70 minutes. The stream was then cooled, and continuously extracted with aqueous sodium bicarbonate and water (twice) to remove the catalyst, p-TsOH. A solution (TMHQ : Compound 1-3a + Compound 1-3b ≤ 20%) was collected, treated with activated carbon, and then mixed with acetic acid (1 equiv) for the hydrogenation in Step 2. The operation steps for Step 1 of the process using the flow reactor as shown in FIG.3 are provided in Table 1 below. Table 1. Operation Steps for Step 1 of Flow Chemistry Process 1. A tubular reactor with 31 m 1/4’’ O.D., 0.047’’ wall thickness PFA tubing was made nd t th fir t t b l r r t r m m m 54 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 The reactor vessel from step 16 was stirred at 15-25 ^C to give a clear solution. NaHCO3 solution was filtered by cartridge filter. 6 1- 4- 5- 0 a a a 55 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [226] Step 2 [227] As shown in FIG. 4, the solution of Compound 1-3a + Compound 1-3b in CPME and hydrogen gas were continuously fed into a fixed-bed reactor containing palladium hydroxide on alumina catalyst for the hydrogenation at 15-40 °C. The reaction was monitored by periodically taking samples from the stream. The solution of Compound 1-4 (Compound 1-3a : Compound 1-4 ≤ 2%) was collected for oxidation in Step 3. The operation steps for Step 2 of the process using the flow reactor as shown in FIG.4 are provided in Table 2 below. Table 2. Operation Steps for Step 2 of Flow Chemistry Process 38. The setup was connected as shown in FIG.4. 39 V l 400 nfirm d l n nd dr d el H ₂ m [228] Step 3 [229] As shown in FIG. 5, the solution of Compound 1-4 obtained from Step 2 was continuously fed into pre-heating tubing at 90 °C, then mixed with 5% O2 gas in the reaction tubing for oxidation. The reaction was monitored by IPC to control Compound 1-4 <0.5%. The reaction stream collected was concentrated under reduced pressure and the solvent was 56 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 exchanged to methanol. The resulting solution was cooled to approximately 30 °C and seeded to induce the crystallization. The crude product was collected by filtration and dried at 30 °C under reduced pressure. The operation steps for Step 3 of the process using the flow reactor as shown in FIG.5 are provided in Table 3 below. Table 3. Operation Steps for Step 3 of Flow Chemistry Process 51. Tubular reactor 502 with 18 m 1/8’’ O.D., 0.02’’ wall thickness stainless steel tubing was made as n. 8- e. e. e. e. 57 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 The reaction vessel was adjusted to 25-35 °C in 2-5 h. 0.9 g (0.003-0.01 X) seed of Compound 1 was charged into the reaction vessel nt as as of of 58 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 [230] Step 4 [231] Crude product from Step 3 was dissolved in approximately 10 volume of acetone and polish filtered. About 1.5 volume of water was then slowly dosed to the resulting solution at room temperature. After seeding at room temperature, an additional 3.5 volumes of water was slowly charged. The resulting suspension was wet milled to D90 < 100 µm, and then filtered. The wet cake was washed and dried at room temperature to afford pure Compound 1. The operation steps for Step 4 of the process using the flow reactor are provided in Table 4 below. Table 4. Operation Steps for Step 4 of Flow Chemistry Process 97. Compound 1 (100g, 1X (0.99-1.01X)) was charged into a reaction vessel. 98 A t 711 711X 632 741X 85V 800900V h d i t th X n 59 1097062200\7\AMERICAS Attorney Docket No.112738.01289 P1671-WO2 112. The third reaction vessel was stirred for 0.5 hr (0.5-15 hr) at 25 °C (20-30 °C). 113. Sample was taken for analysis. IPC of supernatant liquor was taken to determine [232] The disclosures of all publications, patents, patent applications and published patent applications referred to herein by an identifying citation are hereby incorporated herein by reference in their entirety. [233] Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it is apparent to those skilled in the art that certain minor changes and modifications will be practiced. Therefore, the description and examples should not be construed as limiting the scope of the invention. 60 1097062200\7\AMERICAS