BONRATH WERNER (CH)
RIEBEL PETER HANS (CH)
| WO1998023570A1 | 1998-06-04 | |||
| WO2010046199A2 | 2010-04-29 |
| Claims A process for the manufacture of gamma, delta-unsaturated ketones of the general formula R1 O 2/- R RJ by reacting a tertiary vinyl carbinol of the general formula (I) with an isopropenyl alkyl ether of the general formula (II) in the presence of a catalyst of the general formula (IV), (I) (IV) wherein R1 and R6 are independently from each other methyl or ethyl, R3 is methyl, R2 is a saturated or unsaturated linear, branched or cyclic hydrocarbyl group with 1 to 46 C atoms, and R and R' are independently selected from each other from the group consisting of linear Ci-6-alkyl, branched C3-6-alkyl, aryl and aralkyl. 2. The process according to claim 1 , wherein R and R' are identical and selected from the group consisting of methyl, ethyl, propyl, n-butyl, phenyl and benzyl, preferably wherein R and R' are identical and either methyl, phenyl or benzyl. 3. The process according to any one or more of the preceding claims, wherein the reaction is carried out at a temperature ranging from 100 to 170°C, preferably at a temperature ranging from 1 10 to 160°C, more preferably at a temperature ranging from 120 to 150°C. The process according to any one or more of the preceding claims, wherein the reaction is carried out at a pressure ranging from 5 to 15 bar, preferably at a pressure ranging from 8 to 12 bar. The process according to any one or more of the preceding claims, wherein the molar ratio of the tertiary vinyl carbinol of the general formula (I) to the isopropenyl alkyl ether of the general formula (II) is ranging from 1 :7 to 1 : 1 , preferably ranging from 1 :5 to 1 :2, more preferably ranging from 1 :3.5 to 1 :2. The process according to any one or more of the preceding claims, wherein the amount of the catalyst is ranging from 0.01 -0.3 mol-%, preferably ranging from 0.02-0.1 mol-%, more preferably ranging from 0.02-0.07 mol-%, based on the amount of the tertiary vinyl carbinol of the general formula (I). The process according to any one or more of the preceding claims, wherein the compound of the general formula (III) is selected from the group consisting of 6-methyl-5-hepten-2-one, 6-methyl-5-octen-2-one, 6, 10-dimethyl-5,9-undecadien-2-one, 6, 10-dimethyl-5-undecen-2-one and 6, 10, 1 -trimethyl-5,9, 13-pentadeca-trien-2-one, preferably wherein the compound of the general formula (III) is 6-methyl-5- hepten-2-one. Use of a catalyst of the formula (IV) O II RO-P— OR' H (IV) wherein R and R' are independently selected from each other from the group consisting of linear Ci-6-alkyl, branched C3-6-alkyl, aryl and aralkyl, preferably wherein R and R' are identical and selected from the group consisting of methyl, ethyl, propyl, n-butyl, phenyl and benzyl, preferably wherein R and R' are identical and either methyl, phenyl or benzyl, for the manufacture of gamma, delta-unsaturated ketones of the general formula (III ) by reacting a tertiary vinyl carbinol of the general formula (I ) with an iso ropenyl alkyl ether of the general formula (II) wherein R1 and R6 are independently from each other methyl or ethyl, R3 is methyl, and R2 is a saturated or unsaturated linear, branched or cyclic hydrocarbyl group with 1 to 46 C atoms. 9. A reaction mixture comprising a compound of formula (I ), a compound of formula (II ) and a catalyst of formula (IV) (II) (I) (IV) wherein R1 and R6 are independently from each other methyl or ethyl, R3 is methyl, R2 is a saturated or unsaturated linear, branched or cyclic hydrocarbyl group with 1 to 46 C atoms, and R and R' are independently from each other selected from the group consisting of linear Ci-6-alkyl, branched C3-6-alkyl, aryl and aralkyl. 10. A reaction mixture consisting essentially of a compound of formula (I), a compound of formula (II) and a catalyst of formula (IV) (I) (II) (IV) wherein R1 and R6 are independently from each other methyl or ethyl, R3 is methyl, R2 is a saturated or unsaturated linear, branched or cyclic hydrocarbyl group with 1 to 46 C atoms, and R and R' are independently from each other selected from the group consisting of linear Ci-6-alkyl, branched C3-6-alkyl, aryl and aralkyl. |
The present invention is directed towards an industrial sustainable process for the manufacture of gamma, delta-unsaturated ketones of formula (III) in the presence of novel catalysts of formula (IV),
wherein R 1 is methyl or ethyl, R 3 is methyl, R 2 is a saturated or unsaturated linear, branched or cyclic hydrocarbyl group with 1 to 46 C atoms, and R and R' are independently from each other selected from the group consisting of linear Ci- 6 -alkyl, branched C 3 - 6 -alkyl, aryl and aralkyl (see also
FigU)- The present invention is especially directed towards an industrial
sustainable process for the manufacture of 6-methyl-5-hepten-2-one ("MH"; see Fig. 2), 6-methyl-5-octen-2-one ("EH"; see Fig. 3), (5EZ)-6, 10-dimethyl- 5,9-undecadien-2-one (f)-geranylacetone = "GA"; (Z)-nerylacetone = "NA"; see Fig. 4), (5fZ)-6, 10-dimethyl-5-undecen-2-one ((f)-dihydrogeranyl- acetone = "DHGA"; (Z)-dihydronerylacetone = "DHNA"; see Fig. 5) and 6,10,14-trimethyl-5,9,13-pentadeca-trien-2-one (= farnesylacetone; "FA"; see Fig. 6).
Preferred catalysts according to the present invention are "DPPI" (diphenyl phosphite), "DMPI" (dimethyl phosphite) and "DBPI" (dibenzyl phosphite). PhO P OPh MeO P OMe PhCH 2 0 P OCH 2 Ph
H H H
DPPI DMPI DBPI
Detailed description
The present invention is directed towards a process for the manufacture of gamma, delta-unsaturated ketones of the general formula (III)
by reacting a tertiary vinyl carbinol of the general formula (I) with an isopropenyl alkyl ether of the general formula (II) in the presence of a catalyst of the general formula (IV),
wherein R 1 and R 6 are independently from each other methyl or ethyl, R 3 methyl, R 2 is a saturated or unsaturated linear, branched or cyclic hydrocarbyl group with 1 to 46 C atoms, and
R is selected from the group consisting of linear Ci- 6 -alkyl, branched C3-6- alkyl, aryl and aralkyl. Starting materials
Compound of the formula (I)
(I)
R 1 is either methyl or ethyl, and R 2 is a saturated or unsaturated li branched or cyclic hydrocarbyl group with 1 to 46 C atoms.
Preferred examples of R 2 are listed in the following Table 1.
The compound of the general formula (I) is preferably selected from the group consisting of 2-methyl-3-buten-2-ol ("MBE"), 3-methyl-1 -penten-3-ol ("EBE"), 3,7-dimethyl-1 ,6-octadien-3-ol (= linalool, "LL"), 3,7-dimethyl-1 - octen-3-ol ("DMOE"), and (6E/6Z)-3,7, 11 -trimethyl-1 ,6,10-dodecatrien-3-ol (= E/Z-nerolidol, "E/Z-NL").
More preferably the compound of formula (I) is MBE or EBE.
Compound of the formula (II)
The compound of formula (II) is preferably either isopropenyl methyl ether ("IPM") or isopropenyl ethyl ether ("IPE"), whereby isopropenyl methyl ether is more preferred.
Amounts of compounds of the formula (I) and (II)
The molar ratio of the tertiary vinyl carbinol of the general formula (I) to the isopropenyl alkyl ether of the general formula (II) is preferably ranging from 1 :7 to 1 : 1 , more preferably ranging from 1 :5 to 1 :1.5, most preferably ranging from 1 :3.5 to 1 :2.
Catalysts of the formula (IV)
(IV) R and R' are independently from each other selected from the group consisting of linear Ci- 6 -alkyl, branched C 3 - 6 -alkyl, aryl and aralkyl.
Preferably R and R' are independently from each other selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, 2- propyl, 2-butyl, 2-methylprop-1 -yl, tert-butyl, 2-pentyl, 3-pentyl, neopentyl, 2-methylpent-1 -yl, phenyl, 1 -naphthyl, 2-naphthyl and benzyl. More preferred are the catalysts as cited above wherein R and R' are identical.
Even more preferred are catalysts of the formula (IV), wherein R and R' are identical and selected from the group consisting of methyl, ethyl, propyl, n- butyl, phenyl and benzyl. Especially preferred are catalysts of the formula (IV), wherein R and R' are identical and either methyl, n-butyl, phenyl or benzyl, i.e. dimethyl phosphite ("DMPI"), di-n-butyl phosphite ("DNBP"), diphenyl phosphite ("DPPI") and dibenzyl phosphite ("DBPI").
DEPI
PhO P OPh MeO P OMe PhCH 2 0 P OCH 2 Ph
H H H
DPPI DMPI DBPI
Most preferred are DPPI, DMPI and DBPI.
The amount of the catalyst of formula (IV) is preferably ranging from 0.01 - 0.30 mol-%, more preferably ranging from 0.05-0.25 mol-%, most preferably ranging from 0.07-0.20 mol-%, based on the amount of the tertiary vinyl carbinol of the general formula (I).
Advantageously the catalysts of formula (IV) are used as such, but they may also be used as solution in a suitable organic solvent such as e.g. acetone. Reaction conditions
Temperature
The reaction is preferably carried out at a temperature ranging from 100 to 170°C, more preferably at a temperature ranging from 110 to 160°C, most preferably at a temperature ranging from 120 to 150°C.
Pressure
The reaction is preferably carried out at a pressure ranging from 5 to 15 bar, more preferably at a pressure ranging from 8 to 12 bar.
Solvent
The reaction can be carried out without solvent or in the presence of an organic solvent. Preferably the reaction is carried out without solvent. If the reaction is carried out in an organic solvent, polar aprotic organic solvents such as aliphatic ketones as e.g. acetone are preferred.
Even if the reaction is carried out in the absence of an organic solvent, the starting materials, the compounds of formula (I) and (II), as well as the catalyst of formula (IV) may still be provided in an organic solvent. Thus, there may be an amount of organic solvent up to 10 weight-%, preferably an amount of organic solvent up to 5 weight-%, more preferably an amount of organic solvent up to 3 weight-%, based on the total weight of the reaction mixture, present in the reaction mixture.
The reaction mixture itself, with or without an organic solvent, is also an object of the present invention. Thus, the present invention is directed towards a reaction mixture comprising a compound of formula (I), a compound of formula (II) and a catalyst of formula (IV), as well as towards a reaction mixture consisting essentially of a compound of formula (I), a compound of formula II) and a catalyst of formula (IV).
(I) (II) (IV) "consisting essentially of" in this context means that the total amount of the compound of formula (I), the compound of formula (II) and the catalyst of formula (IV) sum up to an amount of at least 90 weight-%, preferably at least 95 weight-%, more preferably at least 97 weight-%, based on the total amount of the reaction mixture.
The present invention is also directed towards the use of a catalyst of formula (IV)
O II
RO-P— OR'
H
(IV) wherein R and R' are independently from each other selected from the group consisting of linear Ci- 6 -alkyl, branched C 3 - 6 -alkyl, aryl and aralkyl, preferably R and R' are independently from each other selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, 2- propyl, 2-butyl, 2-methylprop-1 -yl, tert-butyl, 2-pentyl, 3-pentyl, neopentyl, 2-methylpent-1 -yl, phenyl, 1 -naphthyl, 2-naphthyl and benzyl, more preferably R and R' are identical and selected from the group consisting of methyl, ethyl, propyl, n-butyl, phenyl and benzyl, even more preferably R and R' are identical and selected from the group consisting of methyl, n-butyl, phenyl or benzyl, most preferably R and R' are identical and either methyl, phenyl or benzyl, for the manufacture of gamma, delta-unsaturated ketones of the general formula (III)
by reacting a tertiary vinyl carbinol of the general formula (I) with an isopropenyl alkyl ether of the general formula (II)
wherein R 1 and R 6 are independently from each other methyl or ethyl, R 3 is methyl, and R 2 is a saturated or unsaturated linear, branched or cyclic hydrocarbyl group with 1 to 46 C atoms, whereby the preferences as given above also apply.
The present invention is now further illustrated by the following non- limiting examples. Examples:
General procedure
The powdery catalyst (either DPPI, DMPI or DBPI in the amount as given in table 2 below) is filled into the reactor as such. 144 g of the starting material (MBE) and the amount of IPM ("eq." refers to the molar ratio relative to the other starting material, the compound of formula (I)) as given in table 2 below are mixed and poured into the reactor. The closed reactor is then evacuated and subsequently released with nitrogen three times. The reaction mixture is stirred and heated up to the temperature as given in table 2 below. The experiment is then carried out at isothermal conditions. After the reaction time given in table 2, the reaction mixture is cooled down to 20° C. A sample of the reaction mixture is collected and directly neutralized with sodium acetate. The sample is then analyzed by gas chromatography. Table 2: