TITLE

ELECTROACTIVE COMPOUNDS

CLAIM OF BENEFIT OF PRIOR APPLICATION

This application claims the benefit of U.S. Provisional Application No. 62/881 155, filed July 31 , 2019, which is incorporated in its entirety herein by reference.

BACKGROUND INFORMATION

Field of the Disclosure

This disclosure relates in general to electroactive compounds and their use in electronic devices.

Description of the Related Art

Organic electronic devices that emit light, such as light-emitting diodes that make up displays, are present in many different kinds of electronic equipment. In all such devices, an organic active layer is sandwiched between two electrical contact layers. At least one of the electrical contact layers is light-transmitting so that light can pass through the electrical contact layer. The organic active layer emits light through the light-transmitting electrical contact layer upon application of electricity across the electrical contact layers.

It is well known to use organic electroluminescent compounds as the active component in light-emitting diodes. Simple organic molecules, such as anthracene, thiadiazole derivatives, and coumarin derivatives are known to show electroluminescence. Metal complexes, particularly iridium and platinum complexes are also known to show electroluminescence. In some cases, these small molecule compounds are present as a dopant in a host material to improve processing and/or electronic properties.

There is a continuing need for new electroactive compounds that can be used as hosts or electroluminescent materials.

SUMMARY

There is provided a compound having Formula I

wherein:

Ar ¹ is selected from the group consisting of hydrocarbon aryl groups, heteroaryl groups, and substituted derivatives thereof; Q is selected from the group consisting of Formula Q1 , Formula Q2, and Formula Q3

wherein:

Ar ² is selected from the group consisting of hydrocarbon aryl groups, heteroaryl groups, and substituted derivatives thereof;

Ar ³ is the same or different at each occurrence and is selected from the group consisting of phenyl, naphthyl, and substituted derivatives thereof;

Y is the same or different at each occurrence and is selected from the group consisting of O, S, and Se;

FR represents a fused ring system selected from the group

consisting of fused hydrocarbon aryl rings having an additional 4-18 ring carbons, fused heteroaryl rings having an additional 4-18 ring carbons and at least one ring heteroatom, and substituted derivatives thereof; R ¹ , R ² , and R ⁴ are the same or different at each occurrence and are selected from the group consisting of D, F, CN, alkyl, fluoroalkyl, hydrocarbon aryl, heteroaryl, silyl, germyl, deuterated alkyl, deuterated partially-fluorinated alkyl, deuterated hydrocarbon aryl, deuterated heteroaryl, deuterated heteroaryl deuterated silyl, and deuterated germyl, where adjacent R ² groups can be joined together to form a fused hydrocarbon aromatic ring or heteroaromatic ring;

R ³ is selected from the group consisting of H, D, F, CN, alkyl,

fluoroalkyl, hydrocarbon aryl, heteroaryl, silyl, germyl, deuterated alkyl, deuterated partially-fluorinated alkyl, deuterated hydrocarbon aryl, deuterated heteroaryl, deuterated heteroaryl deuterated silyl, and deuterated germyl;

a is an integer from 0-8;

b is an integer from 0-1 ;

c is an integer from 0-4;

d is an integer from 0-3;

e is an integer from 0 to the maximum number of bonding sites available; and

^* indicates a point of attachment in the identified formula.

There is also provided an organic electronic device comprising a first electrical contact, a second electrical contact and a photoactive layer therebetween, the photoactive layer comprising a compound having Formula I.

The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as defined in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated in the accompanying figures to improve understanding of concepts as presented herein.

FIG. 1 includes an illustration of one example of an organic electronic device including a new compound described herein. FIG. 2 includes an illustration of another example of an organic electronic device including a new compound described herein.

Skilled artisans appreciate that objects in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the objects in the figures may be exaggerated relative to other objects to help to improve understanding of embodiments.

DETAILED DESCRIPTION

Many aspects and embodiments have been described above and are merely exemplary and not limiting. After reading this specification, skilled artisans appreciate that other aspects and embodiments are possible without departing from the scope of the invention.

Other features and benefits of any one or more of the embodiments will be apparent from the following detailed description, and from the claims. The detailed description first addresses Definitions and

Clarification of Terms followed by the Compound Having Formula I, Devices, and finally Examples.

1. Definitions and Clarification of T erms

Before addressing details of embodiments described below, some terms are defined or clarified.

Unless otherwise specifically defined, R, R’, R” and any other variables are generic designations. The specific definitions for a given formula herein are controlling for that formula.

The term“adjacent” as it refers to substituent groups refers to groups that are bonded to carbons that are joined together with a single or multiple bond. Exemplary adjacent R groups are shown below: The term“alkoxy” is intended to mean the group RO-, where R is an alkyl group.

The term“alkyl” is intended to mean a group derived from an aliphatic hydrocarbon and includes a linear, a branched, or a cyclic group. A group“derived from” a compound, indicates the radical formed by removal of one or more H or D.

In some embodiments, an alkyl has from 1-20 carbon atoms.

The term“aromatic compound” is intended to mean an organic compound comprising at least one unsaturated cyclic group having 4n+2 delocalized pi electrons.

The term“aryl” is intended to mean a group derived from an aromatic hydrocarbon having one or more points of attachment. The term includes groups which have a single ring and those which have multiple rings which can be joined by a single bond or fused together.

Hydrocarbon aryl groups have only carbon in the ring structures.

Heteroaryl groups have at least one heteroatom in a ring structure.

The term“alkylaryl” is intended to mean an aryl group having one or more alkyl substituents.

The term“aryloxy” is intended to mean the group RO-, where R is an aryl group.

The term "charge transport," when referring to a layer, material, member, or structure is intended to mean such layer, material, member, or structure facilitates migration of such charge through the thickness of such layer, material, member, or structure with relative efficiency and small loss of charge. Hole transport materials facilitate positive charge; electron transport materials facilitate negative charge. Although light-emitting materials may also have some charge transport properties, the term “charge transport layer, material, member, or structure” is not intended to include a layer, material, member, or structure whose primary function is light emission.

The term“deuterated” is intended to mean that at least one hydrogen (“H”) has been replaced by deuterium (“D”). The term

“deuterated analog” refers to an analog of a compound or group having the same structure, but in which one or more available hydrogens have been replaced with deuterium. In a deuterated compound or deuterated analog, the deuterium is present in at least 100 times the natural abundance level. The term“% deuterated” or“% deuteration” is intended to mean the ratio of deuterons to the sum of protons plus deuterons, expressed as a percentage.

The term“dopant” is intended to mean a material, within a layer including a host material, that changes the electronic characteristic(s) or the targeted wavelength(s) of radiation emission, reception, or filtering of the layer compared to the electronic characteristic(s) or the wavelength(s) of radiation emission, reception, or filtering of the layer in the absence of such material.

The term“germyl” refers to the group RsGe-, where R is the same or different at each occurrence and is H, D, C1 -20 alkyl, deuterated alkyl, fluoroalkyl, aryl, or deuterated aryl.

The prefix“hetero” indicates that one or more carbon atoms have been replaced with a different atom. In some embodiments, the different atom is N, O, or S.

The term“host material” is intended to mean a material, usually in the form of a layer, to which a dopant may be added. The host material may or may not have electronic characteristic(s) or the ability to emit, receive, or filter radiation.

The terms“luminescent material”,“emissive material” and“emitter” are intended to mean a material that emits light when activated by an applied voltage (such as in a light-emitting diode or light-emitting electrochemical cell). The term“blue luminescent material” is intended to mean a material capable of emitting radiation that has an emission maximum at a wavelength in a range of approximately 445-490 nm.

The term "layer" is used interchangeably with the term "film" and refers to a coating covering a desired area. The term is not limited by size. The area can be as large as an entire device or as small as a specific functional area such as the actual visual display, or as small as a single sub-pixel. Layers and films can be formed by any conventional deposition technique, including vapor deposition, liquid deposition (continuous and discontinuous techniques), and thermal transfer. Continuous deposition techniques, include but are not limited to, spin coating, gravure coating, curtain coating, dip coating, slot-die coating, spray coating, and continuous nozzle coating or printing. Discontinuous deposition techniques include, but are not limited to, ink jet printing, gravure printing, and screen printing.

The term“N-heterocycle” or“N-heteroaryl” refers to a

heteroaromatic compound or group having at least one nitrogen in an aromatic ring.

The term“N,0,S-heterocycie” or“N,0,S-heteroaryl” refers to a heteroaromatic compound or group having at least one heteroatom in an aromatic ring, where the heteroatom is N, O, or S. The N,0,S- heterocycle may have more than one type of heteroatom.

The term "organic electronic device" or sometimes just“electronic device” is intended to mean a device including one or more organic semiconductor layers or materials.

The term“photoactive” refers to a material or layer that emits light when activated by an applied voltage (such as in a light emitting diode or chemical cell) or responds to radiant energy and generates a signal with or without an applied bias voltage (such as in a photodetector or a

photovoltaic cell). The photoactive material or layer is sometimes referred to as the emissive layer. The photoactive layer is abbreviated herein as “EML”.

The term“si lacycloal kyl” refers to a cyclic alkyl group where one or more carbons have been replaced with silicons.

The term“silaspirofluorenyl” refers to a spirofluorenyl group where the spiro carbon has been replaced with silicon.

The term“siloxane” refers to the group R3SiO(R2Si)-, where R is the same or different at each occurrence and is H, D, C1-20 alkyl, deuterated alkyl, fluoroalkyl, aryl, or deuterated aryl. In some embodiments, one or more carbons in an R alkyl group are replaced with Si.

The term“siloxy” refers to the group R ₃ SiO-, where R is the same or different at each occurrence and is H, D, C1 -20 alkyl, deuterated alkyl, fluoroalkyl, aryl, or deuterated aryl.

The term“silyl” refers to the group R ₃ S1-, where R is the same or different at each occurrence and is H, D, C1 -20 alkyl, deuterated alkyl, fluoroalkyl, aryl, or deuterated aryl. In some embodiments, one or more carbons in an R alkyl group are replaced with Si.

The term“spirofluorenyl” refers to a group derived from the compound below, where the central carbon is referred to as the spiro carbon.

All groups may be unsubstituted or substituted. The substituent groups are discussed below. In a structure where a substituent bond passes through one or more rings as shown below,

it is meant that the substituent R may be bonded at any available position on the one or more rings.

In any of the formulas or combination of formulas below, any subscript, such as a-h, k, p, q, r, s, a1 , b1 , and k1 , that is present more than one time, may be the same or different at each occurrence.

In this specification, unless explicitly stated otherwise or indicated to the contrary by the context of usage, where an embodiment of the subject matter hereof is stated or described as comprising, including, containing, having, being composed of or being constituted by or of certain features or elements, one or more features or elements in addition to those explicitly stated or described may be present in the embodiment.

An alternative embodiment of the disclosed subject matter hereof, is described as consisting essentially of certain features or elements, in which embodiment features or elements that would materially alter the principle of operation or the distinguishing characteristics of the embodiment are not present therein. A further alternative embodiment of the described subject matter hereof is described as consisting of certain features or elements, in which embodiment, or in insubstantial variations thereof, only the features or elements specifically stated or described are present.

Also, use of“a” or“an” are employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

Group numbers corresponding to columns within the Periodic Table of the elements use the "New Notation" convention as seen in the CRC Handbook of Chemistry and Physics, 81 ^st Edition (2000-2001 ).

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, suitable methods and materials are described below. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

To the extent not described herein, many details regarding specific materials, processing acts, and circuits are conventional and may be found in textbooks and other sources within the organic light-emitting diode display, photodetector, photovoltaic cell, and semiconductive member arts.

2. Compounds Having Formula I

In some embodiments, the compounds described herein have

Formula I

wherein: Ar ¹ is selected from the group consisting of hydrocarbon aryl groups, heteroaryl groups, and substituted derivatives thereof; Q is selected from the group consisting of Formula Q1 , Formula Q2, and Formula Q3

wherein:

Ar ² is selected from the group consisting of hydrocarbon aryl

groups, heteroaryl groups, and substituted derivatives thereof; Ar ³ is the same or different at each occurrence and is selected from the group consisting of phenyl, naphthyl, and substituted derivatives thereof;

Y is the same or different at each occurrence and is selected from the group consisting of O, S, and Se;

FR represents a fused ring system selected from the group

consisting of fused hydrocarbon aryl rings having an additional 4-18 ring carbons, fused heteroaryl rings having an additional 4-18 ring carbons and at least one ring heteroatom, and substituted derivatives thereof;

R ¹ and R ² are the same or different at each occurrence and are selected from the group consisting of D, F, CN, alkyl, fluoroalkyl, hydrocarbon aryl, heteroaryl, silyl, germyl, deuterated alkyl, deuterated partially-fluorinated alkyl, deuterated hydrocarbon aryl, deuterated heteroaryl, deuterated heteroaryl deuterated silyl, and deuterated germyl, where adjacent R ² groups can be joined together to form a fused hydrocarbon aromatic ring or heteroaromatic ring; R ³ is selected from the group consisting of H, D, F, CN, alkyl, fluoroalkyl, hydrocarbon aryl, heteroaryl, silyl, germyl, deuterated alkyl, deuterated partially-fluorinated alkyl, deuterated hydrocarbon aryl, deuterated heteroaryl, deuterated heteroaryl deuterated silyl, and deuterated germyl;

a is an integer from 0-8;

b is an integer from 0-1 ;

c is an integer from 0-4;

d is an integer from 0-3;

e is an integer from 0 to the maximum number of bonding sites available; and

^* indicates a point of attachment in the identified formula.

In some embodiments, the compounds having Formula I are readily sublimable. This is advantageous for purification and for vapor deposition.

In some embodiments, devices including the compounds of Formula I have low operating voltage. In some embodiments, the voltage is less than 5 V at 10 mA/cm ² .; in some embodiments, less than 4.75 V at 10 mA/cm ² .

In some embodiments of Formula I, the compound is deuterated.

In some embodiments, the compound is at least 10% deuterated; in some embodiments, at least 20% deuterated; in some embodiments, at least 30% deuterated; in some embodiments, at least 40% deuterated; in some embodiments, at least 50% deuterated; in some embodiments, at least 60% deuterated; in some embodiments, at least 70% deuterated; in some embodiments, at least 80% deuterated; in some embodiments, at least 90% deuterated; in some embodiments, 100% deuterated.

In some embodiments of Formula I, deuteration is present on the anthracene core group.

In some embodiments of Formula I, deuteration is present on one or both of Ar ¹ and Q.

In some embodiments of Formula I, Ar ¹ is selected from the group consisting of hydrocarbon aryl groups, heteroaryl groups, and substituted derivatives thereof, wherein substituted derivatives have only substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl, and no other substituents.

In some embodiments of Formula I, Ar ¹ is an unsubstituted hydrocarbon aryl.

In some embodiments of Formula I, Ar ¹ is a hydrocarbon aryl or deuterated analog thereof having 6-30 ring carbons; in some

embodiments 6-18 ring carbons.

In some embodiments of Formula I, Ar ¹ is a substituted

hydrocarbon aryl, where the substituent is selected from the group consisting of D, alkyl, silyl, germyl, hydrocarbon aryl, heteroaryl, deuterated alkyl, deuterated silyl, deuterated germyl, deuterated hydrocarbon aryl, and deuterated heteroaryl. In some embodiments, the heteroaryl has heteroatoms selected from the group consisting of O, S, and Se.

In some embodiments of Formula I, Ar ¹ is selected from the group consisting of phenyl, biphenyl, terphenyl, 1-naphthyl, 2-naphthyl, anthracenyl, fluorenyl, phenanthryl, deuterated analogs thereof, and derivatives thereof having one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, hydrocarbon aryl, heteroaryl, deuterated alkyl, deuterated silyl, deuterated germyl, deuterated hydrocarbon aryl, and deuterated heteroaryl. In some embodiments, the heteroaryl has heteroatoms selected from the group consisting of O, S, and Se.

In some embodiments of Formula I, Ar ¹ is selected from the group consisting of phenyl, biphenyl, terphenyl, 1-naphthyl, 2-naphthyl, anthracenyl, fluorenyl, phenanthryl, and derivatives thereof having one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula I, Ar ¹ is selected from the group consisting of phenyl, biphenyl, naphthyl and substituted derivatives thereof.

In some embodiments of Formula I, Ar ¹ is selected from the group consisting of phenyl, biphenyl, naphthyl and deuterated analogs thereof. In some embodiments of Formula I, Ar ¹ is an unsubstituted heteroaryl.

In some embodiments of Formula I, Ar ¹ is a heteroaryl or deuterated analog thereof having 3-30 ring carbons; in some

embodiments 3-18 ring carbons.

In some embodiments of Formula I, Ar ¹ is a substituted heteroaryl, where the substituent is selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula I, Ar ¹ is selected from the group consisting of heteroaryl and deuterated heteroaryl, where the heteroaryl has at least one ring atom which is selected from the group consisting of O and S.

In some embodiments of Formula I, Ar ¹ is an O-heteroaryl having at least one ring atom that is O.

In some embodiments, the O-heteroaryl is derived from a compound selected from the group consisting of furan, benzo[b]furan, benzo[c]furan, dibenzofuran, and substituted derivatives thereof.

In some embodiments of Formula I, Ar ¹ is present and is an S- heteroaryl having at least one ring atom which is S.

In some embodiments, the S-heteroaryl is derived from a compound selected form the group consisting of thiophene,

benzo[b]thiophene, benzo[c]thiophene, dibenzothiophene, and substituted derivatives thereof.

In some embodiments of Formula I Ar ¹ = Q.

In some embodiments of Formula I Ar ¹ ¹ Q.

In some embodiments of Formula I, a = 0.

In some embodiments of Formula I a 1.

In some embodiments of Formula I, a = 2.

In some embodiments of Formula I a 3.

In some embodiments of Formula I a 4.

In some embodiments of Formula I, a = 5.

In some embodiments of Formula I a 6.

In some embodiments of Formula I, a = 7.

In some embodiments of Formula I a 8. In some embodiments of Formula I, a > 0.

In some embodiments of Formula I, a > 0 and at least one R ¹ is selected from the group consisting of D, alkyl, silyl, deuterated alkyl, and deuterated silyl.

In some embodiments of Formula I, a > 0 and at least one R ¹ = D.

In some embodiments of Formula I, a > 0 and at least one R ¹ is a C1-10 alkyl or deuterated alkyl.

In some embodiments of Formula I, a > 0 and at least one R ¹ is a C1-10 silyl or deuterated silyl.

In some embodiments of Formula I, Q has Formula Q1

as defined above.

In some embodiments of Formula Q1 , Y = O.

In some embodiments of Formula Q1 , Y = S.

In some embodiments of Formula Q1 , Y = Se.

In some embodiments of Formula Q1 , Ar ² is an unsubstituted hydrocarbon aryl having 6-30 ring carbons; in some embodiments, 6-12 ring carbons.

In some embodiments of Formula Q1 , Ar ² is a substituted hydrocarbon aryl having 6-30 ring carbons; in some embodiments, 6-12 ring carbons. In some embodiments, the substituted hydrocarbon aryl has one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q1 , Ar ² is an unsubstituted heteroaryl having 3-30 ring carbons; in some embodiments, 6-12 ring carbons. In some embodiments, the heteroaryl has at least one heteroatom selected from the group consisting of O, S, and Se. In some embodiments of Formula Q1 , A r ² is a substituted heteroaryl having 6-30 ring carbons; in some embodiments, 6-12 ring carbons. In some embodiments, the substituted hydrocarbon aryl has one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q1 , Ar ² is selected from the group consisting of phenyl, biphenyl, terphenyl, 1-naphthyl, 2-naphthyl, anthracenyl, fluorenyl, phenanthryl, deuterated analogs thereof, and derivatives thereof having one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, hydrocarbon aryl, heteroaryl, deuterated alkyl, deuterated silyl, deuterated germyl, deuterated hydrocarbon aryl, and deuterated heteroaryl. In some embodiments, the heteroaryl has heteroatoms selected from the group consisting of O, S, and Se.

In some embodiments of Formula Q1 , Ar ² is selected from the group consisting of phenyl, biphenyl, terphenyl, 1-naphthyl, 2-naphthyl, anthracenyl, fluorenyl, phenanthryl, and derivatives thereof having one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q1 , Ar ² is selected from the group consisting of phenyl, biphenyl, naphthyl and substituted derivatives thereof.

In some embodiments of Formula Q1 , Ar ² is selected from the group consisting of phenyl, biphenyl, naphthyl and deuterated analogs thereof.

In some embodiments of Formula Q1 , Ar ² is an unsubstituted heteroaryl.

In some embodiments of Formula Q1 , Ar ² is a heteroaryl or deuterated analog thereof having 3-30 ring carbons; in some

embodiments 3-18 ring carbons.

In some embodiments of Formula Q1 , Ar ² is a substituted heteroaryl, where the substituent is selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl. In some embodiments of Formula Q1 , Ar ² is selected from the group consisting of heteroaryl and deuterated heteroaryl, where the heteroaryl has at least one ring atom which is selected from the group consisting of O and S.

In some embodiments of Formula Q1 , Ar ² is an O-heteroaryl having at least one ring atom that is O.

In some embodiments, the O-heteroaryl is derived from a compound selected from the group consisting of furan, benzo[b]furan, benzo[c]furan, dibenzofuran, and substituted derivatives thereof.

In some embodiments of Formula Q1 , Ar ² is an S-heteroaryl having at least one ring atom which is S.

In some embodiments, the S-heteroaryl is derived from a compound selected form the group consisting of thiophene,

benzo[b]thiophene, benzo[c]thiophene, dibenzothiophene, and substituted derivatives thereof.

In some embodiments of Formula Q1 , b = 0.

In some embodiments of Formula Q1 , b = 1.

In some embodiments of Formula Q1 , b = 1 and Ar ³ is an unsubstituted phenyl group. As used herein, the term“phenyl” includes groups having one or more points of attachment.

In some embodiments of Formula Q1 , b = 1 and Ar ³ is a substituted phenyl group, where the substituent is selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q1 , b = 1 and Ar ³ is an unsubstituted naphthyl group. As used herein, the term“naphthyl” includes groups having one or more points of attachment.

In some embodiments of Formula Q1 , b = 1 and Ar ³ is a substituted naphthyl group, where the substituent is selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q1 , b = 1 and Ar ³ is selected from the group consisting of phenyl, biphenyl, 1 -naphthyl, 2-naphthyl, and derivatives thereof having one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q1 , c = 0.

In some embodiments of Formula Q1 , c = 1.

In some embodiments of Formula Q1 , c = 2.

In some embodiments of Formula Q1 , c = 3.

In some embodiments of Formula Q1 , c = 4.

In some embodiments of Formula Q1 , c > 0.

In some embodiments of Formula Q1 , c > 0 and at least one R ² is D.

In some embodiments of Formula Q1 , c > 0 and at least one R ² is a hydrocarbon aryl or substituted derivative having 6-18 ring carbons.

In some embodiments of Formula Q1 , c > 0 and at least one R ² is selected from the group consisting of phenyl, biphenyl, terphenyl, alkyl- substituted derivatives thereof, silyl-substituted derivatives thereof, and deuterated analogs thereof.

In some embodiments of Formula Q1 , c > 0 and at least one R ² is selected from the group consisting of phenyl, biphenyl, terphenyl, alkyl- substituted derivatives thereof, silyl-substituted derivatives thereof, and deuterated analogs thereof.

In some embodiments of Formula Q1 , c > 2 and two R ² groups on adjacent carbons are joined together to form one or more fused rings. In some embodiments, the fused ring(s) from R ² and the benzo group to which they are fused for a ring system selected from the group consisting of naphthyl, anthracenyl, phenanthryl, fluorenyl, benzofuranyl,

dibenzofuranyl, benzothienyl, dibenzothienyl, alkyl-substituted derivatives thereof, silyl-substituted derivatives thereof, and deuterated analogs thereof. Some exemplary structures are shown below.

where a1 = 0-8; d and c2 = 0-4; f = 0-6; and the other variables are as defined above.

In some embodiments of Formula I, Q has Formula Q2

as defined above.

In some embodiments of Formula Q2, R ³ = H.

In some embodiments of Formula Q2, R ³ = D.

In some embodiments of Formula Q2, R ³ is an unsubstituted hydrocarbon aryl having 6-30 ring carbons; in some embodiments, 6-12 ring carbons.

In some embodiments of Formula Q2, R ³ is a substituted hydrocarbon aryl having 6-30 ring carbons; in some embodiments, 6-12 ring carbons. In some embodiments, the substituted hydrocarbon aryl has one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q2, R ³ is selected from the group consisting of phenyl, biphenyl, terphenyl, 1-naphthyl, 2-naphthyl, anthracenyl, fluorenyl, phenanthryl, deuterated analogs thereof, and derivatives thereof having one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, hydrocarbon aryl, heteroaryl, deuterated alkyl, deuterated silyl, deuterated germyl, deuterated hydrocarbon aryl, and deuterated heteroaryl. In some embodiments, the heteroaryl has heteroatoms selected from the group consisting of O, S, and Se.

In some embodiments of Formula Q2, R ³ is selected from the group consisting of phenyl, biphenyl, terphenyl, 1-naphthyl, 2-naphthyl, anthracenyl, fluorenyl, phenanthryl, and derivatives thereof having one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q2, R ³ is selected from the group consisting of phenyl, biphenyl, naphthyl and substituted derivatives thereof.

In some embodiments of Formula Q2, R ³ is selected from the group consisting of phenyl, biphenyl, naphthyl and deuterated analogs thereof.

In some embodiments of Formula Q2, R ³ is an unsubstituted heteroaryl.

In some embodiments of Formula Q2, R ³ is an unsubstituted heteroaryl having 3-30 ring carbons; in some embodiments, 6-12 ring carbons. In some embodiments, the heteroaryl has at least one heteroatom selected from the group consisting of O, S, and Se.

In some embodiments of Formula Q2, R ³ is a substituted heteroaryl having 6-30 ring carbons; in some embodiments, 6-12 ring carbons. In some embodiments, the substituted hydrocarbon aryl has one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q2, R ³ is selected from the group consisting of heteroaryl and deuterated heteroaryl, where the heteroaryl has at least one ring atom which is selected from the group consisting of O and S.

In some embodiments of Formula Q2, R ³ is an O-heteroaryl having at least one ring atom that is O.

In some embodiments of Formula Q2, R ³ is an S-heteroaryl having at least one ring atom which is S.

In some embodiments of Formula Q2, R ³ is a substituted or unsubstituted alkyl having 1-20 carbon atoms or deuterated analog thereof; in some embodiments, 1-10 carbons. In some embodiments, the substituted alkyl has one or more substituents selected from the group consisting of D, hydrocarbon aryl, and deuterated hydrocarbon aryl.

In some embodiments of Formula Q2, R ³ is an unsubstituted or substituted silyl group having 3-10 carbons. In some embodiments, the substituent is selected from the group consisting of D, hydrocarbon aryl, and deuterated hydrocarbon aryl.

All of the above-described embodiments for Ar ³ , Y, b, and c in Formula Q1 , apply equally to Ar ³ , Y, b, and c in Formula Q2.

In some embodiments of Formula Q2, c > 2 and two R ² groups on adjacent carbons are joined together to form one or more fused rings. In some embodiments, the fused ring(s) from R ² and the benzo group to which they are fused for a ring system selected from the group consisting of naphthyl, anthracenyl, phenanthryl, fluorenyl, benzofuranyl,

dibenzofuranyl, benzothienyl, dibenzothienyl, alkyl-substituted derivatives thereof, silyl-substituted derivatives thereof, and deuterated analogs thereof. Some exemplary structures are shown below.

where the variables are as defined above.

In some embodiments of Formula I, Q has Formula Q3

as defined above.

In some embodiments of Formula Q3, FR represents a fused ring selected from the group consisting of benzene, naphthalene, anthracene, phenanthrene, fluorene, and substituted derivatives thereof. In some embodiments, the substituents are selected from the group consisting of D, F, CN, alkyl, fluoroalkyl, hydrocarbon aryl, heteroaryl, silyl, germyl, deuterated alkyl, deuterated partially-fluorinated alkyl, deuterated hydrocarbon aryl, deuterated heteroaryl, deuterated heteroaryl deuterated silyl, and deuterated germyl. In some embodiments, the substituents are selected from the group consisting of D, alkyl, deuterated alkyl, silyl, and deuterated silyl.

In some embodiments of Formula Q3, FR represents a fused ring selected from the group consisting of benzo[b]furan, benzo[c]furan, dibenzofuran, benzo[b]thiophene, benzo[c]thiophene, dibenzothiophene, and substituted derivatives thereof. In some embodiments, the

substituents are selected from the group consisting of D, F, CN, alkyl, fluoroalkyl, hydrocarbon aryl, heteroaryl, silyl, germyl, deuterated alkyl, deuterated partially-fluorinated alkyl, deuterated hydrocarbon aryl, deuterated heteroaryl, deuterated heteroaryl deuterated silyl, and deuterated germyl. In some embodiments, the substituents are selected from the group consisting of D, alkyl, deuterated alkyl, silyl, and deuterated silyl.

In some embodiments of Formula Q3, FR represents a fused ring selected from the group consisting of naphthalene, fluorene, dibenzofuran, dibenzothiophene, and substituted derivatives thereof.

In some embodiments of Formula Q3, e = 0.

In some embodiments of Formula Q3, e = 1.

In some embodiments of Formula Q3, e = 2.

In some embodiments of Formula Q3, e = 3.

In some embodiments of Formula Q3, e = 4.

In some embodiments of Formula Q3, e > 0.

In some embodiments of Formula Q3, e > 0 and at least one R ⁴ is D.

In some embodiments of Formula Q3, e > 0 and at least one R ⁴ is a hydrocarbon aryl or substituted derivative having 6-18 ring carbons.

In some embodiments of Formula Q3, e > 0 and at least one R ⁴ is selected from the group consisting of phenyl, biphenyl, terphenyl, alkyl- substituted derivatives thereof, silyl-substituted derivatives thereof, and deuterated analogs thereof.

In some embodiments of Formula Q3, e > 0 and at least one R ⁴ is selected from the group consisting of phenyl, biphenyl, terphenyl, alkyl- substituted derivatives thereof, silyl-substituted derivatives thereof, and deuterated analogs thereof.

In some embodiments of Formula Q3, e > 0 and at least one R ⁴ is a substituted or unsubstituted alkyl having 1-20 carbon atoms or deuterated analog thereof; in some embodiments, 1-10 carbons. In some

embodiments, the substituted alkyl has one or more substituents selected from the group consisting of D, hydrocarbon aryl, and deuterated hydrocarbon aryl.

In some embodiments of Formula Q3, e > 0 and at least one R ⁴ is an unsubstituted or substituted hydrocarbon aryl having 6-30 ring carbons; in some embodiments, 6-12 ring carbons. In some embodiments, the substituted hydrocarbon aryl has one or more substituents selected from the group consisting of D, alkyl, silyl, germyl, deuterated alkyl, deuterated silyl, and deuterated germyl.

In some embodiments of Formula Q3, e > 0 and at least one R ⁴ is an unsubstituted or substituted silyl group having 3-10 carbons. In some embodiments, the substituent is selected from the group consisting of D, hydrocarbon aryl, and deuterated hydrocarbon aryl.

All of the above-described embodiments for Ar ² , Ar ³ , Y, and b in Formula Q1 , apply equally to Ar ² , Ar ³ , Y, and b in Formula Q3.

All of the above-described embodiments for R ³ in Formula Q2, apply equally to R ³ in Formula Q3.

Some exemplary structures are shown below.

(Q3-a)

(Q3-b)

(Q3-c)

(Q3-d) (Q3-e)

In the above structures: a double dashed line between two rings indicates that the rings are fused together in any orientation; Z = CR ⁵ R ⁶ , O, S, or Se; R ⁵ and R ⁶ = alkyl, hydrocarbon aryl, or deuterated analog thereof; d1 = 0-3; h = 0-7; k = 0-5; the other variables are as defined above.

In some embodiments of Formula I, there are no amino groups present.

In some embodiments of Formula I, there are no carbazolyl groups present.

In some embodiments of Formula I, there are no N-containing organic groups present.

Any of the above embodiments for Formula I, Formula Q1 , Formula Q2, and Formula Q3 can be combined with one or more of the other embodiments, so long as they are not mutually exclusive. For example, the embodiment in which Q = Q1 can be combined with the embodiment in which b = 1 and Ar ³ is naphthyl, and the embodiment in which Y = O. The same is true for the other non-mutually-exclusive embodiments discussed above. The skilled person would understand which embodiments were mutually exclusive and would thus readily be able to determine the combinations of embodiments that are contemplated by the present application.

The compounds of Formula I can be made using any technique that will yield a C-C, C-N, C-O, C-S, or C-Si bond. A variety of such

techniques are known, such as Suzuki, Yamamoto, Stille, Negishi, and metal-catalyzed C-N couplings as well as metal catalyzed and oxidative direct arylation.

Deuterated compounds can be prepared in a similar manner using deuterated precursor materials or, more generally, by treating the non- deuterated compound with deuterated solvent, such as benzene-d6, in the presence of a Bronsted or Lewis acid H/D exchange catalyst, such as trifluoromethanesulfonic acid, aluminum trichloride or ethyl aluminum dichloride. Deuteration reactions have also been described in published PCT application WO201 1/053334.

Exemplary preparations are given in the Examples.

Examples of compounds having Formula I include, but are not limited to, the compounds shown below.

Compound 1-1

Compound 1-4

Compound 1-7

Compound 2-1

Compound 3-2 Compound 3-4

Compound 3-8

2. Devices

Organic electronic devices that may benefit from having one or more layers comprising the compounds having Formula I described herein include, but are not limited to, (1 ) devices that convert electrical energy into radiation (e.g., a light-emitting diode, light emitting diode display, diode laser, or lighting panel), (2) devices that detect a signal using an electronic process (e.g., a photodetector, a photoconductive cell, a photoresistor, a photoswitch, a phototransistor, a phototube, an infrared (“IR”) detector, or a biosensors), (3) devices that convert radiation into electrical energy (e.g., a photovoltaic device or solar cell), (4) devices that convert light of one wavelength to light of a longer wavelength, (e.g., a down-converting phosphor device);(5) devices that include one or more electronic components that include one or more organic semiconductor layers (e.g., a transistor or diode), or any combination of devices in items (1 ) through (5).

In some embodiments, the device includes a photoactive layer having a compound of Formula I.

In some embodiments, the device includes an anode and a cathode with a photoactive layer therebetween, where the photoactive layer includes a compound having Formula I.

One illustration of an organic electronic device structure is shown in FIG. 1. The device 100 has a first electrical contact layer, an anode layer 1 10 and a second electrical contact layer, a cathode layer 160, and a photoactive layer (“EML”) 140 between them. Adjacent to the anode is a hole injection layer (“HIL”) 120. Adjacent to the hole injection layer is a hole transport layer (“HTL”) 130, comprising hole transport material.

Adjacent to the cathode may be an electron transport layer (“ETL”) 150, comprising an electron transport material. As an option, devices may use one or more additional hole injection or hole transport layers (not shown) next to the anode 1 10 and/or one or more additional electron injection layer (“El L”) or electron transport layer (not shown) next to the cathode 160. As a further option, devices may have an anti-quenching layer (not shown) between the photoactive layer 140 and the electron transport layer 150.

Layers 120 through 150, and any additional layers between them, are individually and collectively referred to as the active layers.

In some embodiments, the photoactive layer is pixelated, as shown in FIG. 2. In device 200, layer 140 is divided into pixel or subpixel units 141 , 142, and 143 which are repeated over the layer. Each of the pixel or subpixel units represents a different color. In some embodiments, the subpixel units are for red, green, and blue. Although three subpixel units are shown in the figure, two or more than three may be used.

In some embodiments, the different layers have the following range of thicknesses: anode 1 10, 50-500 nm, in some embodiments, 100-200 nm; hole injection layer 120, 5-200 nm, in some embodiments, 20-100 nm; hole transport layer 130, 5-200 nm, in some embodiments, 20-100 nm; photoactive layer 140, 1-200 nm, in some embodiments, 10-100 nm;

electron transport layer 150, 5-200 nm, in some embodiments, 10-100 nm; cathode 160, 20-1000 nm, in some embodiments, 30-500 nm. The location of the electron-hole recombination zone in the device, and thus the emission spectrum of the device, can be affected by the relative thickness of each layer. The desired ratio of layer thicknesses will depend on the exact nature of the materials used.

In some embodiments, the compounds having Formula I are useful as the emissive material in photoactive layer 140, having blue emission color. They can be used alone or as a dopant in a host material.

In some embodiments, the compounds having Formula I are useful as the host material in photoactive layer 140.

a. Photoactive Laver

In some embodiments, the photoactive layer includes a host material and a compound having Formula I as a dopant. In some embodiments, a second host material is present.

In some embodiments, the photoactive layer includes only a host material and a compound having Formula I as a dopant. In some embodiments, minor amounts of other materials, are present so long as they do not significantly change the function of the layer.

In some embodiments, the photoactive layer includes a dopant and a compound having Formula I as host. In some embodiments, a second host material is present. In some embodiments, more than one dopant is present.

Compounds having Formula I can be used as hosts with a variety of dopants and will perform in a similar way. Dopants are well known and broadly disclosed in the patent literature and technical journals.

Exemplary dopants include, but are not limited to, anthracenes, benzanthracenes, benz[de]anthracenes, chrysenes, pyrenes,

triphenylenes, benzofluorenes, other polycyclic aromatics, and analogs having one or more heteroatoms. Exemplary dopants also include, but are not limited to, benzofurans, dibenzofurans, carbazoles,

benzocarbazoles, carbazolocarbazoles, and azaborines. In some embodiments, the dopants have one or more diarylamino substituents. Dopants have been disclosed in, for example, US 7,816,017, US

8,465,848, US 9,1 12,157, US 2006/0127698, US 2010/0032658, US 2018/0069182, US 2019/0058124, CA 3107010, EP 3109253, WO

2019003615, and WO 2019035268.

In some embodiments, the photoactive layer includes a blue luminescent material as dopant and a compound having Formula I as host.

In some embodiments, the photoactive layer includes only a dopant material and a compound having Formula I as host. In some

embodiments, minor amounts of other materials are present, so long as they do not significantly change the function of the layer.

In some embodiments, the photoactive layer includes only a dopant material, a compound having Formula I as host, and a second host material. In some embodiments, minor amounts of other materials are present, so long as they do not significantly change the function of the layer.

The weight ratio of total dopant to total host material is in the range of 2:98 to 70:30; in some embodiments, 5:95 to 70:30; in some

embodiments, 10:90 to 20:80.

In some embodiments, the second host material is selected from the group consisting of anthracenes, chrysenes, pyrenes, phenanthrenes, triphenylenes, phenanthrolines, naphthalenes, triazines, quinolines, isoquinolines, quinoxalines, phenylpyridines, benzodifurans, metal quinolinate complexes, indolocarbazoles, substituted derivatives thereof, and combinations thereof.

Any of the compounds of Formula I represented by the

embodiments, specific embodiments, specific examples, and combination of embodiments discussed above can be used in the photoactive layer. b. Other Device Lavers

The other layers in the device can be made of any materials which are known to be useful in such layers.

The anode 1 10 is an electrode that is particularly efficient for injecting positive charge carriers. It can be made of, for example materials containing a metal, mixed metal, alloy, metal oxide or mixed-metal oxide, or it can be a conducting polymer, and mixtures thereof. Suitable metals include the Group 1 1 metals, the metals in Groups 4, 5, and 6, and the Group 8-10 transition metals. If the anode is to be light-transmitting, mixed-metal oxides of Groups 12, 13 and 14 metals, such as indium-tin- oxide, are generally used. The anode may also be made of an organic material such as polyaniline as described in“Flexible light-emitting diodes made from soluble conducting polymer,” Nature vol. 357, pp 477 479 (1 1 June 1992). At least one of the anode and cathode should be at least partially transparent to allow the generated light to be observed.

The hole injection layer 120 includes hole injection material and may have one or more functions in an organic electronic device, including but not limited to, planarization of the underlying layer, charge transport and/or charge injection properties, scavenging of impurities such as oxygen or metal ions, and other aspects to facilitate or to improve the performance of the organic electronic device. The hole injection layer can be formed with polymeric materials, such as polyaniline (PANI) or polyethylenedioxythiophene (PEDOT), which are often doped with protonic acids. The protonic acids can be, for example, poly(styrenesulfonic acid), poly(2-acrylamido-2-methyl-1 -propanesulfonic acid), and the like.

The hole injection layer can include charge transfer compounds, and the like, such as copper phthalocyanine, 1 ,4,5,8,9,12- hexaazatriphenylenehexacarbonitrile (HAT-CN), and the

tetrathiafulvalene-tetracyanoquinodimethane system (TTF-TCNQ).

In some embodiments, the hole injection layer includes at least one electrically conductive polymer and at least one fluorinated acid polymer.

Examples of hole transport materials for layer 130 have been summarized for example, in Kirk-Othmer Encyclopedia of Chemical Technology, Fourth Edition, Vol. 18, p. 837-860, 1996, by Y. Wang. Both hole transporting molecules and polymers can be used. Commonly used hole transporting molecules are: N,N'-diphenyl-N,N'-bis(3-methylphenyl)- [1 ,T-biphenyl]-4,4'-diamine (TPD), 1 ,1 -bis[(di-4-tolylamino)

phenyljcyclohexane (TAPC), N,N'-bis(4-methylphenyl)-N,N'-bis(4- ethylphenyl)-[1 ,T-(3,3'-dimethyl)biphenyl]-4,4'-diamine (ETPD), tetrakis-(3- methylphenyl)-N,N,N',N'-2,5-phenylenediamine (PDA), a-phenyl-4-N,N- diphenylaminostyrene (TPS), p-(diethylamino)benzaldehyde

diphenylhydrazone (DEH), triphenylamine (TPA), bis[4-(N,N- diethylamino)-2-methylphenyl](4-methylphenyl)methane (MPMP), 1-phenyl-3-[p-(diethylamino)styryl]-5-[p-(diethylamino)pheny l] pyrazoline (PPR or DEASP), 1 ,2-trans-bis(9H-carbazol-9-yl)cyclobutane (DCZB), N,N,N',N'-tetrakis(4-methylphenyl)-(1 ,T-biphenyl)-4,4'-diamine (TTB), N,N’-bis(naphthalen-1-yl)-N,N’-bis-(phenyl)benzidine (a-NPB), and porphyrinic compounds, such as copper phthalocyanine. In some embodiments, the hole transport layer includes a hole transport polymer.

In some embodiments, the hole transport polymer is a distyrylaryl compound. In some embodiments, the aryl group has two or more fused aromatic rings. In some embodiments, the aryl group is an acene. The term“acene” as used herein refers to a hydrocarbon parent component that contains two or more orf/70-fused benzene rings in a straight linear arrangement. Other commonly used hole transporting polymers are polyvinylcarbazole, (phenylmethyl)-polysilane, and polyaniline. It is also possible to obtain hole transporting polymers by doping hole transporting molecules such as those mentioned above into polymers such as polystyrene and polycarbonate. In some cases, triarylamine polymers are used, especially triarylamine-fluorene copolymers. In some cases, the polymers and copolymers are crosslinkable.

In some embodiments, the hole transport layer further includes a p- dopant. In some embodiments, the hole transport layer is doped with a p- dopant. Examples of p-dopants include, but are not limited to,

tetrafluorotetracyanoquinodimethane (F4-TCNQ) and perylene-3,4,9,10- tetracarboxylic-3, 4, 9, 10-dianhydride (PTCDA).

In some embodiments, more than one hole transport layer is present (not shown).

Examples of electron transport materials which can be used for layer 150 include, but are not limited to, metal chelated oxinoid

compounds, including metal quinolate derivatives such as tris(8- hydroxyquinolato)aluminum (AIQ), bis(2-methyl-8-quinolinolato)(p- phenylphenolato) aluminum (BAIq), tetrakis-(8-hydroxyquinolato)hafnium (HfQ) and tetrakis-(8-hydroxyquinolato)zirconium (ZrQ); and azole compounds such as 2- (4-biphenylyl)-5-(4-t-butylphenyl)-1 ,3,4-oxadiazole (PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-t-butylphenyl)-1 ,2,4-triazole (TAZ), and 1 ,3,5-tri(phenyl-2-benzimidazole)benzene (TPBI); quinoxaline derivatives such as 2,3-bis(4-fluorophenyl)quinoxaline; fluoranthene derivatives, such as 3-(4-(4-methylstyryl)phenyl-p-tolylamino)fluoranthene; phenanthrolines such as 4,7-diphenyl-1 ,10-phenanthroline (DPA) and 2,9- dimethyl-4,7-diphenyl-1 ,10-phenanthroline (DDPA); and mixtures thereof.

In some embodiments, the electron transport layer further includes an n- dopant. N-dopant materials are well known. The n-dopants include, but are not limited to, Group 1 and 2 metals; Group 1 and 2 metal salts, such as LiF, CsF, and CS2CO3; Group 1 and 2 metal organic compounds, such as Li quinolate; and molecular n-dopants, such as leuco dyes, metal complexes, such as W2(hpp)4 where hpp=1 ,3,4,6,7,8-hexahydro-2H- pyrimido-[1 ,2-a]-pyrimidine and cobaltocene, tetrathianaphthacene, bis(ethylenedithio)tetrathiafulvalene, heterocyclic radicals or diradicals, and the dimers, oligomers, polymers, dispiro compounds and polycycles of heterocyclic radical or diradicals.

In some embodiments, an anti-quenching layer may be present between the photoactive layer and the electron transport layer to prevent quenching of blue luminance by the electron transport layer. To prevent energy transfer quenching, the singlet energy of the anti-quenching material has to be higher than the singlet energy of the blue emitter. To prevent electron transfer quenching, the LUMO level of the anti-quenching material has to be shallow enough (with respect to the vacuum level) such that electron transfer between the emitter exciton and the anti-quenching material is endothermic. Furthermore, the HOMO level of the anti quenching material has to be deep enough (with respect to the vacuum level) such that electron transfer between the emitter exciton and the anti quenching material is endothermic. In general, anti-quenching material is a large band-gap material with high singlet and triplet energies.

The cathode 160, is an electrode that is particularly efficient for injecting electrons or negative charge carriers. The cathode can be any metal or nonmetal having a lower work function than the anode. Materials for the cathode can be selected from alkali metals of Group 1 (e.g., Li, Cs), the Group 2 (alkaline earth) metals, the Group 12 metals, including the rare earth elements and lanthanides, and the actinides. Materials such as aluminum, indium, calcium, barium, samarium and magnesium, as well as combinations, can be used.

Alkali metal-containing inorganic compounds, such as LiF, CsF, CS2O and U2O, or Li-containing organometallic compounds can also be deposited between the organic layer 150 and the cathode layer 160 to lower the operating voltage. This layer, not shown, may be referred to as an electron injection layer.

It is known to have other layers in organic electronic devices. For example, there can be a layer (not shown) between the anode 1 10 and hole injection layer 120 to control the amount of positive charge injected and/or to provide band-gap matching of the layers, or to function as a protective layer. Layers that are known in the art can be used, such as copper phthalocyanine, silicon oxy-nitride, fluorocarbons, silanes, or an ultra-thin layer of a metal, such as Pt. Alternatively, some or all of anode layer 1 10, active layers 120, 130, 140, and 150, or cathode layer 160, can be surface-treated to increase charge carrier transport efficiency. The choice of materials for each of the component layers is preferably determined by balancing the positive and negative charges in the emitter layer to provide a device with high electroluminescence efficiency.

It is understood that each functional layer can be made up of more than one layer.

c. Device Fabrication

The device layers can be formed by any deposition technique, or combinations of techniques, including vapor deposition, liquid deposition, and thermal transfer.

In some embodiments, the device is fabricated by liquid deposition of the hole injection layer, the hole transport layer, and the photoactive layer, and by vapor deposition of the anode, the electron transport layer, an electron injection layer and the cathode. Suitable liquid deposition techniques are well known in the art. In some embodiments, all the device layers are fabricated by vapor deposition. Such techniques are well known in the art.

EXAMPLES

The concepts described herein will be further described in the following examples, which do not limit the scope of the invention described in the claims.

Synthesis Examples

These examples illustrate the preparation of compounds having Formula I, as described above. In the examples, the following abbreviations are used:

B2pin2 = bis(pinacolato)diboron

Pd2(dba)3 = Tris(dibenzylideneacetone)dipalladium(0)

S-Phos = 2-Dicyclohexylphosphino-2',6'-dimethoxybiphenyl

Synthesis Example 1

This example illustrates the preparation of a compound having Formula I, Compound 1 -1.

2-phenyl-3-[4-(10-phenylanthracen-9-yl)phenyl]-1 -benzofuran.

Inside a glovebox, Pd2(dba)3 (0.178 g, 0.194 mmol), S-Phos (0.637 g, 1.55 mmol), 3-(4-chlorophenyl)-2-phenylbenzofuran (5.90 g, 19.36 mmol), and 4,4,5,5-tetramethyl-2-(10-phenylanthracen-9-yl)-1 ,3,2- dioxaborolane (7.73 g, 20.32 mmol) and 1 ,4-dioxane (16 mL) was added to a 250-mL round-bottom flask. The flask was sealed with a septum. In the fume hood, K ₃ PO ₄ H ₂ O (33.5 g, 145.5 mmol) monohydrate was added followed by 30 mL of Dl water in a 40-mL vial. The mixture was swirled until a clear solution was observed. The vial was sealed with a septum- lined cap and sparged with nitrogen from for 50 min. The reaction flask was brought out of the glovebox, the aqueous tribasic potassium phosphate (20 ml_, 5 M) was added via a gastight syringe. The reaction mixture was stirred at 1 10 °C for 15 h. The product was purified by silica gel chromatography to give a white powder (4.34 g, 42%). ¹ H NMR

(CH2CI ₂ -62, 499.8 MHz) 57.91 -7.88 (m, 4H), 7.81 -7.74 (m, 5H), 7.68-7.61 (m, 6H), 7.53 (m, 2H), 7.50-7.37 (m, 9H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69

MHz) 5 154.6, 151.3, 139.4, 138.8, 137.7, 137.1 , 132.5, 132.4, 131.7, 131.2, 130.6, 130.3(4), 130.3(1 ), 130.2, 128.9(8), 128.9(7), 128.8(6), 128.0, 127.6, 127.4, 127.2, 125.6, 125.5, 125.3, 123.5, 120.5, 1 17.8, 1 1 1.5. APCr (m/z) calculated for 0 ₄ oH ₂₆ 0 ([M+H] ⁺ ) 523.21 , found 522.63.

Synthesis Example 2

This example illustrates the preparation of a compound having Formula I, Compound 1 -2.

2-(naphthalen-1 -yl)-3-[4-(10-phenylanthracen-9-yl)phenyl]-1 -benzofuran.

Inside a glovebox, Pd2(dba)3 (0.239 g, 0.261 mmol), S-Phos (0.845 g, 2.06 mmol), 3-(4-chlorophenyl)-2-(naphthalen-1-yl)benzofuran (7.27 g, 20.5 mmol), and 4,4,5,5-tetramethyl-2-(10-phenylanthracen-9-yl)-1 ,3,2- dioxaborolane (8.20 g, 21 .6 mmol) were combined in a 500-mL round- bottom flask. 1 ,4-Dioxane (105 ml_) was added. The flask was fitted with a reflux head and sealed with a rubber septum. Outside the box, a 40-mL vial was charged with K3PO4 monohydrate (47.8 g, 208 mmol) was added followed by deionized water (42 ml_). The mixture was swirled until a clear solution was observed. The vial was sealed with a septum-lined cap and sparged with nitrogen for 45 min. The reaction flask was brought out of the glovebox, 21 mL of the aqueous tribasic potassium phosphate was added via an airtight syringe. The reaction mixture was stirred at 1 10 °C for 26 h. The product was purified by silica gel chromatography and crystallization to give a white powder (4.48 g, 7.82 mmol). ¹ H NMR (CH2CI2 -d _å , 499.8 MHz) d 8.04-7.99 (m, 3H), 7.96 (m, 1 H), 7.85 (m, 1 H), 7.72-7.55 (m, 12H), 7.50-7.44 (m, 5H), 7.36-7.31 (m, 6H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) 5 155.4, 151.8, 139.4, 138.3, 137.6, 137.1 , 134.3, 132.4, 132.0, 131.7, 131.6(6), 130.3, 130.2(6), 130.2(5), 130.2, 129.9, 129.4, 129.1 , 128.8(2), 128.8(0), 128.7, 127.9, 127.3, 127.2, 126.9, 126.6, 126.5, 125.7, 125.4,

125.2, 123.6, 120.7, 1 19.9, 1 1 1 .9. APCI ⁺ (m/z) calculated for C ₄₄ H ₂₈ 0 ([M] ⁺ ) 572.21 , found 572.48.

Synthesis Example 3

This example illustrates the preparation of a compound having

Formula I, Compound 1 -3.

2-phenyl-3-(10-phenylanthracen-9-yl)-1 -benzofuran.

In a 200-mL round bottome flask, 9-bromo-10-phenyl-anthracene (4.962 g, 14.89 mmol), 2-phenyl-3-(4,4,5,5-tetramethyl-1 ,3,2-dioxaborolan-

2-yl)benzofuran (5.035 g, 15.72 mmol) and potassium phosphate tribasic monohydrate (17.192 g, 74.656 mmol) were combined. The flask was fitted with a reflux condenser on the larger neck; the smaller neck was fitted with a septum. The flask was evacuated and vent 3 times with nitrogen. The final cycle placed the flask under a positive atmosphere of nitrogen. A 20-mL scintillation vial was charged with 20 ml_ of Dl water.

The vial was capped with a Teflon septum. The water was sparged with nitrogen for 50 min. In the glovebox, a 100-mL pear-shape flask was charged with palladium and S-phos. 1 ,4-Dioxane was then added. The mixture was stirred for 5 min. The flask was then sealed and brought out of the glovebox. During that time, water (10 ml_) was transferred to the reaction flask via a gas-tight syringe. The mixture was heated at 80 °C for 3 h. The product was purified to give a white powder (4.15 g, 62%). ¹ H NMR (CH ₂ CI 2-d ₂ , 499.8 MHz) 57.83 (d, J = 8.6 Hz, 2H), 7.79 (d, J = 8.7 Hz, 2H), 7.75 (d, J = 8.3 Hz, 1 H), 7.70-7.65 (m, 2H), 7.63-7.60 (m, 2H), 7.57 (m, 1 H), 7.49 (m, 2H), 7.41 (m, 1 H), 7.36 (m, 2H), 7.30 (m, 2H), 7.20- 7.12 (m, 4H), 6.91 (m, 1 H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) 5 154.6, 152.5, 139.2, 138.9, 132.4, 131 .7(4), 131.7(2), 131 .0, 130.8, 130.7(9), 128.9(4), 128.9(3), 128.8(9), 128.8(6), 128.7, 128.1 , 127.8, 127.0, 126.6,

126.2, 126.1 (8), 125.7, 125.5, 123.5, 120.8, 1 14.0, 1 1 1.6. APCI ⁺ (m/z) calculated for C34H22O ([M] ⁺ ) 446.17, found 446.42.

Synthesis Example 4

This example illustrates the preparation of a compound having

Formula I, Compound 1 -4.

2-phenyl-3-[3-(10-phenylanthracen-9-yl)phenyl]-1 -benzofuran.

Inside a glovebox, a 250-mL round-bottom flask was charged with Pd ₂ (dba) ₃ (0.151 g, 0.165 mmol), S-Phos (0.539 g, 1.31 mmol) and 1 ,4 dioxane (80 mL). The mixture was stirred for ten minutes. Then, 3-(3- bromophenyl)-2-phenylbenzofuran (5.70 g, 16.3 mmol), 4, 4,5,5- tetramethyl-2-(10-phenylanthracen-9-yl)-1 ,3,2-dioxaborolane (6.829 g, 17.95 mmol) were added. In a fume hood, potassium phosphate tribasic monohydrate (28 g, 0.12 mmol) was dissolved in deionized water (24 mL). The solution was sparged for 40 min. The reaction mixture was removed from the box and the base solution (16 mL) was added via an gas-tight syringe. The mixture was stirred at 80 °C for 3 h. The product was purified by recrystallization to give a white solid (5.23 g, 61 %). ¹ H NMR (CH ₂ CI ₂ -d ₂ , 499.8 MHz) 5 7.82-7.76 (m, 6H), 7.70-7.67 (m, 3H), 7.64-7.52 (m, 6H),

7.48 (m, 1 H), 7.44 (m, 1 H), 7.41-7.28 (m, 9H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ ,

125.69 MHz) 5 154.6, 151.3, 140.3, 139.4, 137.7, 137.0, 133.5, 132.9, 131.7, 131.6, 131.0(4), 131.0(3), 130.5, 130.2(67), 130.2(59), 129.6, 129.3, 128.9, 128.8(9), 128.8(3), 128.8(1 ), 127.9, 127.6, 127.3, 127.2, 125.5, 125.4, 125.2, 123.5, 120.4, 1 17.7, 1 1 1.5. APCI ⁺ (m/z) calculated for C40H26O ([M] ⁺ ) 522.20, found 522.48. Synthesis Example 5

This example illustrates the preparation of a compound having Formula I, Compound 2-1.

3-phenyl-2-[4-(10-phenylanthracen-9-yl)phenyl]-1 -benzofuran.

In a 2-neck 500-mL flask, 4,4,5,5-tetramethyl-2-(10- phenylanthracen-9-yl)-1 ,3,2-dioxaborolane (9.093 g, 23.91 mmol), 2-(4- chlorophenyl)-3-phenylbenzofuran (6.94 g, 22.8 mmol) and potassium phosphate tribasic monohydrate (27.0 g, 1 17 mmol) were combined with 1 ,4-dioxane (104 ml_) and deionized water (23 ml_). The flask was fitted with a reflux condenser on the larger neck; the smaller neck was fitted with a septum. The mixture was sparged with nitrogen for 50 min. In the glovebox, a 100-mL pear shape flask was charged with Pd2(dba)3 (0.210 g, 0.229 mmol) and S-Phos (0.750 g, 1.83 mmol). 1 ,4-dioxane (10 ml_) was then added. The mixture was stirred for 10 min. The flask was then sealed and brought out of the glovebox and the solution was transferred to the reaction flask via cannula. The reaction mixture was stirred at 1 10 °C for 20 h. The product was purified to give a white powder (10.466 g, 88%). ¹ H NMR (CH2CI 2-cf ₂ , 499.8 MHz) 5 7.95 (m, 2H), 7.75 (m, 2H), 7.70-7.54 (m, 1 1 H), 7.48-7.44 (m, 5H), 7.42-7.29 (m, 6H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) 5 154.5, 150.7, 139.7, 139.4, 137.8, 136.8, 133.3, 131.9,

131.7, 130.9, 130.4, 130.2(79), 130.2(71 ), 130.1 (7), 129.5, 128.8, 128.2, 127.9, 127.3, 127.2, 127.1 , 125.6, 125.5, 125.3, 123.5, 120.4, 1 18.4,

1 1 1.5. APC (m/z) calculated for 0 ₄ oH ₂₆ 0 ([M+H] ⁺ ) 523.21 , found 522.65. Synthesis Example 6 This example illustrates the preparation of a compound having Formula I, Compound 2-2.

(a) 2-Bromo-2-(4-bromophenyl)acetophenone

Bromine (17.6 g, 1 10.1 mmole) was added dropwise over period of approx. 15 min to a stirring suspension of 2-(4-bromophenyl)- acetophenone (25.3 g, 91 .95 mmole) in 200 ml of acetic acid and the reaction mixture was stirred at ambient temperature overnight. After that crude mixture filtered, washed with methanol, hexanes, dried to give 13.1 g of the product. Filtrate diluted with water, allowed to stand for solidification of the product, filtration, dried in vacuum to give additional 14.65 g of the product. Total yield - 27.75 g (85%). ¹ H-NMR (CDCIs, 500 MHz): 6.30 (s, 1 H), 7.42 (d, 2H, J = 9 Hz), 7.46-7.52 (m, 4H), 7.59 (t, 1 H, J = 8 Hz), 7.99 (dd, 2H, J1 = 9 Hz, J2 = 1 Hz).

(b) 9-Phenanthrenol

To a stirred solution of 9-phenanthreneboronic acid in 200 ml of tetrahydrofuran was added 22 g of 50%wt aqueous sodium hydroxide, reaction mixture cooled to approx. 5C followed by addition of 33 g of 30% hydrogen peroxide aqueous solution within approx. 20 min maintaining internal temperature in the range 20-37C. After that reaction mixture diluted with 1 L of water, extracted with ethyl acetate (4 times). Combined ethyl acetate extracts passed through a short plug of silica gel eluated with ethyl acetate. The residue evaporated to volume approx. 50 ml, passed again through a short plug of silica gel eluated with ethyl acetate. The residue after evaporation of ethyl acetate treated with hexanes, dried to give 19.63 g (90%) of 9-phenanthrenol. ¹ H-NMR (CDCIs, 500 MHz): 6.91

(s, 1 H), 6.97 (t, 1 H, J = 9 Hz), 7.02 (t, 1 H, J = 8 Hz), 7.14 (t, 1 H, J= 8 Hz), 7.18-7.22 (m, 3H), 7.88 (d, 1 H, J = 9 Hz), 8.09 (d, 2H, J = 8 Hz), 8.18 (d, 1 H, J = 8 Hz), 9.34 (br s, 1 H).

(c) 2-(4-Bromophenyl)-3-phenyl-phenanthro[9,10-b]furan.

A mixture of 9-phenanthrenol (6.86 g, 35.31 mmole), 2-bromo-2-(4- bromophenyl)acetophenone (12.5 g, 35.31 mmole), neutral aluminum oxide (30 g), toluene (100 ml) was heated at 1 10C under inert atmosphere with stirring for 16 hours. After that the mixture cooled down, filtered, washed with toluene (50 ml), filtrate diluted with 150 ml of hexanes.

Precipitate formed filtered to give 0.56 g of bis-phenanthryl ether side product. Filtrate was passed through a short plug of silica washing with mixture of hexanes - dichloromethane 2:1 and resulting solution was allowed to stand for 30 min, precipitate filtered off again. Filtrate evaporated in vacuum to minimal volume followed by addition of approx. 50 ml of dichloromethane and hexanes. Resulting precipitate was collected portion wise diluting with hexanes to give 5.61 g of crude product that was used for the next step without further purification. ¹ H-NMR (CDCIs, 500 MHz): 7.35 (t, 1 H), 7.45 (d, 2H, J = 9 Hz), 7.49 (d, 2H, J = 9 Hz), 7.54-7.63 (m, 7H), 7.71 (td, 1 H, J1 = 8 Hz, J2 = 1 Hz), 7.76 (td, 1 H, J1 = 8 Hz, J2 = 1 Hz), 8.51 (dd, 1 H, J1 = 6 Hz, J2 = 1 Hz), 8.73-8.76 (m, 2H).

(d) 2-(4-(4,4,5,5-T etramethyl-1 ,3,2-dioxaborolan-2-yl)phenyl)-3-phenyl- phenanthro[9, 10-b]furan

A mixture of the above 2-(4-bromophenyl)-3-phenyl- phenanthro[9,10-b]furan (5.61 g, 12.48 mmole), bis(pinacolato)diboron (3.49 g, 13.73 mmole), potassium acetate (6.12 g, 62.4 mmole), (1 ,1 - bis(diphenylphosphino)ferrocene)palladium(ll) dichloride (0.913 g, 1.248 mmole), 1 ,4-dioxane (100 ml) was heated at 100C with stirring under nitrogen atmosphere for 1 .5 hours. Reaction mixture cooled down, passed through a filter filled with silica gel and celite eluating with

dichloromethane, solvents evaporated using rotary evaporator, the residue dissolved in dichloromethane, evaporated onto celite and subjected to chromatography purification on silica gel column using gradient eluation with mixtures of hexanes and dichloromethane. Fractions containing product combined, eluent evaporated, the residue dried in vacuum to give 2.816 g of product. ¹ H-NMR (CD ₂ CI ₂ , 500 MHz): 1 .34 (s, 12 H), 7.35 (t,

1 H, J = 8 Hz), 7.56 (t, 1 H, J = 8 Hz), 7.60-7.62 (m, 7H), 7.69-7.73 (m, 3H), 7.78 (t, 1 H, J = 8 Hz), 8.55 (dd, 1 H, J1 = 8 Hz, J2 = 1 Hz), 8.74-8.77 (m,

2H).

(e) 3-Phenyl-2-[4-(10-phenyl-9-anthracenyl)-phenyl]- phenanthro[9,10-b]furan, Compound 2-2.

A mixture of 9-bromo-10-phenylanthracene (1 .715 g, 5.146 mmole), 2-(4-(4,4,5,5-tetramethyl-1 ,3,2-dioxaborolan-2-yl)phenyl)-3- phenyl-phenanthro[9,10-b]furan (2.81 g, 5.661 mmole), Pd2(dba)3 ( 94 mg, 0.103 mmole), SPhos (338 mg, 0.823 mmole), potassium phosphate (5.46 g, 25.73 mmole), toluene (50 ml), water (10 ml), ethanol (20 ml) was heated at 100C with stirring under nitrogen atmosphere for 20 hours. Reaction mixture cooled down, precipitate filtered, washed with toluene, water, dried in vacuum to give crude product (2.2 g). The product was dissolved in hot chloroform (100 ml), passed through a filter filled with silica gel, florisil and basic alumina, eluated with chloroform. Chloroform evaporated to volume approx. 20 ml and solution was allowed to stand to crystallize at ambient temperature. Precipitate collected by filtration, dried in vacuum to give 1.78 g of Compound 2-2 with purity 99.74%. ¹ H-NMR (CDCIs, 500 MHz): 7.34-7.40 (m, 5H), 7.45 (d, 2H, J = 9 Hz), 7.48-7.50 (m, 2H), 7.58-7.76 (m, 15H), 7.81 (t, 1 H, J = 8 Hz), 7.92 (d, 2H, J = 8 Hz),

8.61 (d, 1 H, J = 8 Hz), 7.78-7.81 (m, 2H). MS: 623.

Synthesis Example 7

This example illustrates the preparation of a compound having

Formula I, Compound 3-1.

2-phenyl-6-(10-phenylanthracen-9-yl)benzo[d]benzo[1 ,2-b:5,4-b']difuran.

Into a 20-mL vial, Pd2(dba)3 (0.005 g, 0.005 mmol), S-Phos (0.018 g, 0.044 mmol), 6-chloro-2-phenylbenzo[d]benzo[1 ,2-b:5,4-b']difuran (0.1574 g, 0.493 mmol), and 4,4,5,5-tetramethyl-2-(10-phenyl-9- anthracenyl)-1 ,3,2-dioxaborolane (0.291 g, 0.763 mmol) were combined. Dioxane (2.5 ml_) was added. The vial was sealed with a septum. To a 4- mL vial, K ₃ PO ₄ monohydrate was added followed by 1 ml_ of Dl water. The mixture was swirled until a clear solution was observed. The vial was sealed with a septum-lined cap and sparged with nitrogen for 20 min. The base solution (0.5 ml_) was transferred to the reaction vial. The reaction mixture was stirred at 1 10 °C for 19 h. After cooling, the vial was washed with DCM (20 ml_) and the suspension was transferred to a 200-mL recovery flask. The mixture was concentrated on the rotavap to dryness. Then the mixture was stirred in DCM (50 ml_). To the suspension, MeOH (50 ml_) was added. The mixture was stirred for 10 min. Then the suspension was filtered and washed with deionized water (20 mL) then MeOH (25 mL). It was dried to constant weight to give 243 mg (92% yield) of a white powder. APCI ⁺ (m/z) calculated for C ₄₀ H ₂₄ O ₂ ([M+H] ⁺ ) 537.18, found 536.57

Synthesis Example 8

This example illustrates the preparation of a compound having Formula I, Compound 3-2.

2-phenyl-7-(10-phenylanthracen-9-yl)naphtho[2, 1 -b]furan.

In a 2-neck 200-mL round-bottom flask, 9-bromo-10-phenyl- anthracene (3.333 g, 10.00 mmol), 2-phenyl-7-(4,4,5,5-tetramethyl-1 ,3,2- dioxaborolan-2-yl)- naphtho[2,1 -b]furan (3.890 g, 10.51 mmol) and K ₃ PO ₄ (1 1 .429 g, 49.63 mmol) were combined. The flask was fitted with a reflux condenser on the larger neck; the smaller neck was fitted with a septum. The flask was evacuated and vent 3 times with nitrogen. The final cycle placed the flask under a positive atmosphere of nitrogen. A 20-mL scintillation vial was charged with 15 mL of Dl water. The vial was capped with a Teflon septum. The water was sparged with nitrogen for >20 min. In the glovebox, a 100-mL pear shape flask was charged with Pd ₂ (dba) ₃

(0.095 g, 0.10 mmol) and S-Phos (0.331 g, 0.807 mmol). 1 ,4-Dioxane (50 mL) was then added. The mixture was stirred for 5 min. The flask was then sealed and brought out of the glovebox. During that time, water (10 mL) was transferred to the reaction flask via a gas-tight syringe. The catalyst solution was transferred to the reaction flask via a cannula. The reaction mixture was stirred at 80 °C for 2 h. After cooling the room temperature, the reaction suspension was poured into a plastic filter funnel. The cake was rinsed with toluene (20 mL), followed by MeOH (50 mL) with agitation of the cake, then Dl water (60 mL) with agitation, then MeOH (50 mL) with agitation. The cake was then purified by chromatography to give a white solid (4.15 g, 84%). APCI ⁺ (m/z) calculated for Cssh^O ([M+H] ⁺ ) 497.19, found 496.74.

Synthesis Example 9

This example illustrates the preparation of a compound having

Formula I, Compound 3-3.

2-phenyl-5-(10-phenylanthracen-9-yl)benzofuran.

In a 2-neck 500-mL round-bottom flask, 9-bromo-10-phenyl- anthracene (10.01 g, 30.01 mmol), 4,4,5,5-tetramethyl-2-(2- phenylbenzofuran-5-yl)-1 ,3,2-dioxaborolane (10.1 g, 31.5 mmol) and potassium phosphate tribasic monohydrate (35.8 g, 155 mmol) were combined with 1 ,4-dioxane (130 ml_), and deionized water (30 ml_0. The flask was fitted with a reflux condenser on the larger neck; the smaller neck was fitted with a septum. The mixture was sparged with nitrogen for 30 min. In the glovebox, a 100-mL pear shape flask was charged with Pd ₂ (dba) ₃ (0.278 g, 0.304 mmol) and S-Phos (0.989 g, 2.41 mmol). 1 ,4- Dioxane (10 mL) was then added. The mixture was stirred for 10 min. The flask was then sealed and brought out of the glovebox, and the solution was transferred to the reaction flask via a cannula. The reaction mixture was stirred at 80 °C for 3.5 h. The product was purified by column chromatography and recrystallization to give a white powder (6.914 g, 52%). ¹ H NMR (CH2CI 2-d ₂ , 499.8 MHz) 5 7.99 (d, J = 7.2 Hz, 2H), 7.80- 7.71 (m, 6H), 7.68-7.59 (m, 3H), 7.56-7.51 (m, 4H), 7.33-7.46 (m, 6H), 7.18 (s, 1 H). APCr (m/z) calculated for Cs^O ([M+H] ⁺ ) 447.17, found

446.54.

Synthesis Example 10

This example illustrates the preparation of a compound having Formula I, Compound 3-4.

1 ,2-diphenyl-7-(10-phenylanthracen-9-yl)naphtho[2, 1 -b].

Inside a glovebox, a 100-mL round-bottom flask was charged with Pd2(dba)3 (0.052 g, 0.057 mmol), S-Phos (0.145 g, 0.353 mmol) and 1 ,4 dioxane (33 ml_). The mixture was stirred for 5 minutes. Then, 9-bromo- 10-phenyl-anthracene (2.488 g, 7.466 mmol), 1 ,2-diphenyl-7-(4,4,5,5- tetramethyl-1 ,3,2-dioxaborolan-2-yl)naphtho[2,1-b]furan (3.512 g, 7.868 mmol), potassium phosphate tribasic (7.926 g, 37.22 mmol) and dioxane (30 ml_) were added. The flask was sealed with a septum and brought out of the glovebox. Degassed and deionized water was added (7.5 ml_). The mixture was stirred at 80 °C for about 5 h. The product was purified to give a white solid (3.2 g, 75%). ¹ H NMR (CH ₂ CI ₂ -d ₂ , 499.8 MHz) 5 8.05 (m, 1 H), 7.86 (m, 2H), 7.79 (d, J = 8.4 Hz, 1 H), 7.71-7.56 (m, 14H), 7.50-7.48 (m, 2H), 7.38 (m, 1 H), 7.35-7.26 (m, 7H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) 5 152.1 , 150.8, 139.4, 137.6, 137.3, 135.3, 135.0, 131.7, 131.6(9),

131.6(8), 131.4, 131.3, 131.0, 130.5, 130.3, 129.9, 128.9, 128.8, 128.7(7), 128.4, 128.0, 127.9, 127.3, 127.2(9), 126.7, 126.5, 125.4(4), 125.4(2), 124.2, 123.5, 120.1 , 1 13.1. APCP (m/z) calculated for C ₄ oH ₂₆ 0 ([M] ⁺ ) 572.71 , found 572.40.

Synthesis Example 1 1

This example illustrates the preparation of a compound having Formula I, Compound 3-5.

2,3-diphenyl-5-(10-phenylanthracen-9-yl)-1 -benzofuran Inside a glovebox, Pd2(dba)3 (0.178 g, 0.194 mmol), S-Phos (0.637 g, 1.55 mmol), 3-(4-chlorophenyl)-2-phenylbenzofuran (5.90 g, 19.36 mmol), and 4,4,5,5-tetramethyl-2-(10-phenylanthracen-9-yl)-1 ,3,2- dioxaborolane (7.73 g, 20.32 mmol) and 1 ,4-dioxane (16 ml_) were added to a 250-mL round-bottom flask. The flask was sealed with a septum. In the fume hood, K ₃ PO ₄ H ₂ O (33.5 g, 145.5 mmol) monohydrate was added followed by 30 mL of Dl water in a 40-mL vial. The mixture was swirled until a clear solution was observed. The vial was sealed with a septum- lined cap and sparged with nitrogen from for 50 min. The reaction flask was brought out of the glovebox, the aqueous tribasic potassium phosphate (20 mL, 5 M) was added via a gastight syringe. The reaction mixture was stirred at 1 10 °C for 15 h. The product was purified by silica gel chromatography to give a white powder (4.34 g, 42%). ¹ H NMR

(CH2CI ₂ -62, 499.8 MHz) d7.91-7.88 (m, 4H), 7.81 -7.74 (m, 5H), 7.68-7.61 (m, 6H), 7.53 (m, 2H), 7.50-7.37 (m, 9H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69

MHz) 8154.6, 151 .3, 139.4, 138.8, 137.7, 137.1 , 132.5, 132.4, 131.7, 131.2, 130.6, 130.3(4), 130.3(1 ), 130.2, 128.9(8), 128.9(7), 128.8(6), 128.0, 127.6, 127.4, 127.2, 125.6, 125.5, 125.3, 123.5, 120.5, 1 17.8, 1 1 1.5. APC (m/z) calculated for 0 ₄ oH ₂₆ 0 ([M] ⁺ ) 522.19, found 522.63.

Synthesis Example 12

This example illustrates the preparation of a compound having Formula I, Compound 3-6.

2-phenyl-4-(10-phenylanthracen-9-yl)-1 -benzofuran

Inside a glovebox, Pd2(dba)3 (0.193 g, 0.21 mmol) and S-Phos (0.691 g, 0.807 mmol) were charged to a round-bottom flask. 1 ,4-Dioxane (105 mL) was then added. The mixture was stirred for 10 min. Then, 9- bromo-10-phenyl-anthracene (7.01 g, 21.0 mmol), 4,4,5,5-tetramethyl-2-(2- phenylbenzofuran-4-yl)-1 ,3,2-dioxaborolane (7.07 g, 22.1 mmol) were charged into the flask. Meanwhile, a solution of K ₃ PO ₄ was prepared by combining K ₃ PO ₄ (36 g, 3.45 mmol) with deionized water (32 ml_). The solution was sparged with nitrogen for 50 min. The reaction flask was fitted with a reflux condenser, sealed with septa and removed from the glovebox. The solution of base was transferred to the flask via a gas-tight syringe. The reaction mixture was heated to a set temperature of 80 °C and stirred for about 3 h. The product was purified to give a white solid (7.6885 g, 81 %). ¹ H NMR (CH ₂ CI ₂ -62, 499.8 MHz) d 7.76-7.73 (m, 5H), 7.68-7.64 (m, 4H), 7.61-7.51 (m, 4H), 7.38-7.29 (m, 8H), 6.48 (s, 1 H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ ,

125.69 MHz) 5 156.7, 155.3, 139.4, 132.4, 131.7(3), 131 .6(7), 131 .1 , 130.6, 130.4, 130.3(8), 129.1 , 129.0, 128.8(8), 128.8(7), 128.0, 127.4, 127.2, 126.3, 125.7, 125.5, 125.2, 124.8, 1 10.9, 101.5, APCI ⁺ (m/z) calculated for C ₃₄ H ₂₂ O ([M] ⁺ ) 446.17, found 446.62.

Synthesis Example 13

This example illustrates the preparation of a compound having Formula I, Compound 1 -5.

2-phenyl-3-(4-(10-phenylanthracen-9-yl)naphthalen-1 -yl)benzofuran

In a fume hood, 4-(2-phenylbenzofuran-3-yl)naphthalen-1 -yl trifluoromethanesulfonate (1.30 g, 2.78 mmol), 4,4,5,5-tetramethyl-2-(10- phenylanthracen-9-yl)-1 ,3,2-dioxaborolane (1.601 g, 4.21 mmol), and sodium carbonate (0.888 g, 8.38 mmol) were charged into a 250-mL round-bottom flask. Then toluene (18 ml_), water (3 ml_), and ethanol (4 ml_) were added. The mixture was sparged with nitrogen for 25 min. Inside the glovebox, tetrakis(triphenylphosphine)palladium (0.160 g, 0.139 mmol) was added to a 100-mL flask, followed by toluene (10 ml_). The flask was sealed with rubber septum and brought out of the glovebox. The catalyst solution was transferred to the reaction flask via cannula. The reaction mixture was stirred at 1 10 °C for about 16 h. The product was purified to give a white solid (0.715 g, 45%). ¹ H NMR (CH ₂ CI ₂ -62, 499.8 MHz) d 7.93 (m, 1 H), 7.83 (m, 1 H), 7.80 (m, 2H), 7.75-7.71 (m, 4H), 7.69-7.66 (m, 2H), 7.64-7.57 (m, 5H), 7.45 (m, 1 H), 7.41-7.25 (m, 12H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) 8154.0, 151 .6, 139.0, 137.8, 137.3, 134.8, 134.2, 132.5,

131.5, 131.3(3), 131.3(1 ), 130.6(8), 130.6(6), 130.6(2), 130.6(0), 130.0, 129.9(9), 129.3(3), 128.5, 128.4(7), 128.4, 128.2, 127.6, 127.1 , 127.0(9), 126.9(9), 126.8(9), 126.7(6), 126.4(7), 126.4(3), 126.4(1 ), 126.3, 125.4 , 125.3, 125.2, 125.1 , 124.9, 123.1 , 120.4, 1 15.8, 1 1 1.1. APCI ⁺ (m/z) calculated for C ₄₄ H ₂₈ 0 ([M] ⁺ ) 572.2, found 572.39.

Synthesis Example 14

This example illustrates the preparation of a compound having Formula I, Compound 3-7.

2-phenyl-5-(10-phenylanthracen-9-yl)naphtho[1 ,2-b]furan

Inside a glovebox, Pd ₂ (dba)3 (0.093 g, 0.10 mmol) and S-Phos (0.338 g, 0.823 mmol) were charged to a round-bottom flask. 1 ,4-Dioxane (50 ml_) was then added. The mixture was stirred for 10 min. Then, 9- bromo-10-phenyl-anthracene (3.430 g, 10.29 mmol), 4,4,5,5-tetramethyl- 2-(2-phenylnaphtho[1 ,2-J ]furan-5-yl)-1 ,3,2-dioxaborolane (4.023 g, 10.80 mmol) were charged into the flask. Meanwhile, a solution of K ₃ P0 ₄ was prepared by combining K3PC (18 g, 78 mmol) with deionized water (15 mL). The solution was sparged with nitrogen for 35 min. The reaction flask was fitted with a reflux condenser, sealed with septa and removed from the glovebox. The solution of base was transferred to the flask via a gas- tight syringe. The reaction mixture was heated to a set temperature of 80 °C and stirred for about 5.5 h. The product was purified to give a white solid (2.93 g, 57%). ¹ H NMR (CH ₂ CI ₂ -62, 499.8 MHz) d 8.61 (m, 1 H), 8.08 (m, 2H), 7.79-7.74 (m, 3H), 7.70-7.60 (m, 5H), 7.87-7.55 (m, 3H), 7.52- 7.50 (m, 2H), 7.44 (m, 1 H), 7.35-7.32 (m, 2H), 7.30 (s, 1 H), 7.26-7.22 (m, 3H), 7.16 (m, 1 H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) 8155.8, 150.4, 139.0, 137.6, 135.1 , 132.3, 131.6, 131 .3(4), 131 .3(0), 130.9(7), 130.6, 130.0, 128.9, 128.4(4), 128.4(3), 127.5, 127.3, 127.0, 126.9, 126.5, 125.3, 125.1 , 125.0(5), 124.7(2), 124.7(0), 122.8, 121 .5, 120.2, 102.5. APCI ⁺ (m/z) calculated for C38H24O ([M] ⁺ ) 496.18, found 496.38.

Synthesis Example 15

This example illustrates the preparation of a compound having Formula I, Compound 3-8.

2,3-diphenyl-4-(10-phenylanthracen-9-yl)-1 -benzofuran

Inside a fume hood, 4,4,5,5-tetramethyl-2-(10-phenylanthracen- 9-yl)-1 ,3,2-dioxaborolane (2.94 g, 7.73 mmol), 2,3-diphenyl-1-benzofuran- 4-yl trifluoromethanesulfonate (3.079 g, 7.36 mmol) and K ₃ PO ₄ (7.2972 g, 34.38 mmol) were charged to a 100-mL round-bottom flask. The flask was fitted with a reflux condenser and attached to a manifold. Three cycles of evacuation and venting with nitrogen were performed. In the glovebox, a pear-shape flask was charged with Pd ₂ (dba)3 (0.071 g, 0.078 mmol), S- Phos (0.239 g, 0.582 mmol). 1 ,4-dioxane (40 mL) was added. The catalyst mixture was stirred for 5 min. The flask was sealed with a septum and brought out of the glovebox. During that time, deionized water (8 mL) was sparged with nitrogen gas. The catalyst solution was transferred to the reaction flask via cannula followed by the deionized water. The reaction mixture was stirred at 105 °C for about 19 h. The product was purified by silica gel chromatography and recrystallization to give a white powder (1 .40 g, 39%). ¹ H NMR (CH ₂ CI ₂ -62, 499.8 MHz) d 7.80 (m, 1 H), 7.62-7.55 (m, 5H), 7.48-7.43 (m, 4H), 7. 83 (m, 2H), 7.32 (m, 1 H), 7.27-7.17 (m, 7H). ¹³ C NMR (CH2CI 2-d ₂ , 125.69 MHz) d 154.4, 151 .1 , 139.6, 137.1 , 133.9, 133.1 , 132.1 , 131.6, 131 .4, 131.0, 130.7, 130.4, 129.8, 129.1 , 128.6(77), 128.6(70), 128.6(6), 12835, 127.7m 127.2, 127.0, 126.8, 126.7, 126.6, 126.5, 125.2, 125.0, 124.9(8), 1 19.2, 1 10.9. APCI ⁺ (m/z) calculated for

C40H26O ([M] ⁺ ) 522.19, found 522.81.

Synthesis Example 16

This example illustrates the preparation of a compound having Formula I, Compound 3-9.

7-(10-(naphthalen-1 -yl)anthracen-9-yl)-1 ,2-diphenylnaphtho[2, 1 -J ]furan

Inside a glovebox, Pd2(dba)3 (0.0588 g, 0.064 mmol) and S- Phos (0.210 g, 0.514 mmol) were charged to a round-bottom flask. 1 ,4- dioxane (32 ml_) was then added. The mixture was stirred for 10 min. Then, 9-bromo-10-phenyl-anthracene (2.286 g, 5.971 mmol), 2-(1 ,2- diphenylnaphtho[2, 1 -b]furan-7-yl)-4,4,5,5-tetramethyl-1 ,3,2-dioxaborolane (2.801 g, 6.275 mmol) were charged into the flask. The flask was sealed with septum and brought outside of the glovebox. Meanwhile, a solution of K ₃ PO ₄ monohydrate was prepared by combining K ₃ PO ₄ (1 1 g, 48 mmol) with deionized water (9 ml_). The base solution was sparged with nitrogen for 30 min. The reaction flask was charged with 6 ml_ of the base solution via a gas-tight syringe. The reaction mixture was heated to a set temperature of 80 °C and stirred for about 3.5 h. The product was purified to give a white solid (2.00 g, 54%). ¹ H NMR (CH ₂ CI ₂ -62, 499.8 MHz) d 8.20-8.12 (m, 2H), 8.06 (m, 1 H), 7.90-7.85 (m, 3H), 7.77-7.60 (m, 1 1 H), 7.55-7.50 (m, 1 H), 7.48-7.45 (m, 2H), 7.35-7.17 (m, 9H). ¹³ C NMR

(CH2CI 2-cf ₂ , 125.69 MHz) d 151 .7, 150.4(6), 150.4(5), 137.4, 136.7(2), 136.7(0), 135.1 , 135.0, 134.9(1 ), 134.9(0), 134.6, 133.8, 133.6, 131.4(7), 131.4(5), 131.1 , 130.9, 130.7, 130.6(1 ), 130.6(0), 130.2, 130.1 (8), 129.5(7), 129.5(6), 129.5(4), 129.5(3), 129.2(4), 129.2(2), 128.5, 128.3(9), 128.3(8), 128.3(2), 128.1 , 128.0, 127.7, 127.1 (0), 127.0(9), 126.9, 126.8(9), 126.4, 126.3(7), 126.2(9), 126.2(8), 126.2(5), 126.2(4), 126.1 (7), 126.1 (5), 126.0, 125.7, 125.2, 125.1 , 123.8(3), 123.8(2), 123.1 , 1 19.7, 1 19.6(9), 1 12.7. APCI ⁺ (m/z) calculated for C ₄₈ H ₃ oO ([M] ⁺ ) 622.23, found

622.57.

Synthesis Example 17

This example illustrates the preparation of a compound having Formula I, Compound 1 -6.

2-phenyl-5-(10-phenylanthracen-9-yl)benzofuran

Inside a glovebox, Pd ₂ (dba) ₃ (0.109 g, 0.1 19 mmol) and S-Phos (0.391 g, 0.952 mmol) were charged to a round-bottom flask. 1 ,4-Dioxane (60 mL) was then added. The mixture was stirred for 10 min. Then, 3-(10- bromoanthracen-9-yl)-9-phenyl-9H-carbazole (5.76 g, 1 1.6 mmol), 4, 4,5,5- tetramethyl-2-(2-phenylbenzofuran-3-yl)-1 ,3,2-dioxaborolane (3.88 g, 12.1 mmol) were charged into the flask. The flask was sealed with septum and brought outside of the glovebox. Meanwhile, a solution of K ₃ P0 ₄ was prepared by combining K ₃ P0 ₄ monohydrate (13.8 g, 59.9 mmol) with deionized water (12 mL). The base solution was sparged with nitrogen for 25 min. The reaction flask was charged with the base solution via a cannula. The reaction mixture was heated to a set temperature of 80 °C and stirred for about 3.5 h. The product was purified to give a white solid (4.48 g, 63%). ¹ H NMR (CH ₂ CI ₂ -d ₂ , 499.8 MHz) d 8.36 (m, 1 H), 8.17 (m,

1 H), 7.90 (d, J = 8.7 Hz, 2H), 7.84 (J = 8.3 Hz, 2H), 7.76-7.68 (m, 6H), 7.64-7.47 (m, 6H), 7.41 (m, 1 H), 7.36-7.29 (m, 5H), 7.20-7.13 (m, 4H),

6.94 (m, 1 H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) 8154.6,

152.5(1 ), 152.5(0), 141.8, 140.9, 139.6, 138.1 , 132.4(3), 132.4(2), 131.5, 131.0(3), 131.0(2), 130.9, 130.6, 130.4, 129.7, 129.6(8), 128.9(7), 128.9(5), 128.8, 128.7, 128.2(3), 128.2(2), 128.1 , 127.5, 126.8, 126.7, 126.6,126.2, 125.6, 125.5, 125.4, 124.0, 123.9, 123.7, 123.6(6), 123.5(3), 123.5(1 ), 123.4(9), 120.8, 120.6, 120.5(6), 1 14.1 , 1 1 1 .6, 1 10.4, 1 10.1 (5), 1 10.1 (1 ). APCr (m/z) calculated for C46H ₂₉ NO ([M] ⁺ ) 61 1.22, found 61 1.47.

Synthesis Example 18

This example illustrates the preparation of a compound having Formula I, Compound 1 -7.

9-(4-(3-(4-chlorophenyl)benzofuran-2-yl)phenyl)-9/-/-carbazo le Inside a glovebox, Pd ₂ (dba)3 (0.0241 g, 0.0256 mmol) and S-Phos (0.0853 g, 0.205 mmol) were charged to a round-bottom flask. 1 ,4- Dioxane (3 mL) was then added. The mixture was stirred for 5 min. Then, 9-(4-(3-(4-chlorophenyl)benzofuran-2-yl)phenyl)-9/-/-carbazo le (1 .2 g, 2.6 mmol), 4,4,5,5-tetramethyl-2-(10-phenylanthracen-9-yl)-1 ,3,2- dioxaborolane (1.1 1 g, 2.69 mmol) and 1 ,4-dioxane (5 mL) were charged into the flask. Meanwhile, a solution of KsPC was prepared by combining K ₃ PC> ₄ -H ₂ 0 (2.99 g, 12.8 mmol) with deionized water (3 mL) in a 20-mL vial. The solution was sparged with nitrogen for 45 min. The reaction flask was fitted with a reflux condenser, sealed with septa and removed from the glovebox. The solution of base was transferred to the flask via a cannula. The reaction mixture was heated to a set temperature of 1 10 °C and stirred for about 24 h. The product was purified to give a white solid (1 .258 g, 71 %). ¹ H NMR (CH ₂ CI ₂ -62, 499.8 MHz) d 8.17-8.12 (m, 4H),

7.89-7.87 (m, 4H), 7.79 (d, J = 7.6 Hz, 1 H), 7.73-7.53 (m, 12H), 7.51-7.29 (m, 12H). ¹³ C NMR (CH ₂ CI ₂ -d ₂ , 125.69 MHz) d 154.7, 150.5, 141 .0, 139.4, 139.1 , 138.1 , 137.8, 137.1 , 132.6, 132.4, 131.7, 130.7, 130.3(5), 130.3(0), 130.1 , 128.9, 128.8, 128.0, 127.4, 127.3, 127.2, 126.5, 125.6, 125.5(6), 125.5(0), 123.9, 123.7, 120.7, 120.6, 1 18.4, 1 1 1.6, 1 10.3. APCI ⁺ (m/z) calculated for C52H33NO ([M] ⁺ ) 687.26, found 687.45. Synthesis Example 19

This example illustrates the preparation of a compound having Formula I, Compound 3-10.

2,3-diphenyl-5-(10-phenylanthracen-9-yl)naphtho[2,3-J ]furan

In a fume hood, 9-bromo-10-phenyl-anthracene (2.774 g, 8.32 mmol), 2,3-diphenyl-5-(4,4,5,5-tetramethyl-1 ,3,2-dioxaborolan-2-yl)- naphtho[2,3-b]furan (3.765 g, 8.44 mmol) and K3PO4 monohydrate (9.58 g, 41 .6 mmol) were charged into a 100-mL round-bottom flask. The flask was evacuated and venting with nitrogen for 3 cycles. During that time, deionized water (8.5 ml_) was sparged with nitrogen. Inside a glovebox, Pd2(dba)3 (0.075 g, 0.082 mmol) and S-Phos (0.304 g, 0.741 mmol) were charged to a pear-shape flask. 1 ,4-Dioxane (44 ml_) was then added. The mixture was stirred for 5 min. The flask containing the catalyst solution was sealed with a septum and then removed from the glovebox. The reaction flask was fitted with a reflux condenser, sealed with septa and removed from the glovebox. The solution transferred to the reaction flask via a cannula. The reaction mixture was heated to a set temperature of 80 °C and stirred for about 2.5 h. The product was purified to give a white solid (3.95 g, 83%). ¹ H NMR (CH ₂ CI ₂ -62, 499.8 MHz) d 8.22 (d, J = 8.4 Hz, 1 H), 8.15 (s, 1 H), 7.73-7.70 (m, 3H), 7.68-7.58 (m, 5H), 7.54-7.49 (m, 5H),

7.34-7.31 (m, 5H), 7.24-7.18 (m, 4H), 7.14-7.08 (m, 4H). ¹³ C NMR

(CH2CI ₂ -cf ₂ , 125.69 MHz) 8153.4, 153.3, 139.5, 137.9, 137.2, 135.7, 132.7, 132.4, 131.9, 131.8, 131 .7, 131.2, 131.0, 130.7, 130.4, 129.7, 129.3, 129.1 , 128.8(3), 128.8(2), 128.8(0), 128.5, 128.3, 128.0, 127.9, 127.8, 127.4, 127.3, 125.5, 125.4, 125.2, 1 17.3, 1 17.2(7), 107.2. APCI ⁺ (m/z) calculated for C ₄₄ H ₂₈ 0 ([M] ⁺ ) 572.2, found 572.40.

Device Examples

These examples illustrate the utility of compounds having Formula I in electronic devices.

(1 ) Materials

ET-1 is a triazine derivative.

ET-2 is a fluorene substituted triazine.

LiQ is lithium quinolate.

HAT-CN is 1 ,4,5,8,9,12-hexaazatriphenylenehexacarbonitrile.

Comparative Host-2 is a dibenzofuran substituted mono-aryl anthracene. Dopant-1 is a di-arylamino pyrene.

Dopant-2 is a boron-containing polycyclic aromatic compound.

HTM-1 is a fluorene substituted arylamine.

HTM-2 is a mono-arylamino phenanthrene.

HTM-3 is a mono-arylamino carbazole.

HTM-4 is a carbazole substituted di-arylamine.

(2) Devices

The emissive layers were deposited by vapor deposition as detailed below. In all cases, prior to use the substrates were cleaned ultrasonically in detergent, rinsed with water and subsequently dried in nitrogen.

(3) Device characterization

The OLED devices were characterized by measuring their

(1 ) current-voltage (l-V) curves, (2) electroluminescence radiance versus voltage, and (3) electroluminescence spectra versus voltage. All three measurements were performed at the same time and controlled by a computer. The current efficiency of the device at a certain voltage is determined by dividing the electroluminescence radiance of the LED by the current density needed to run the device. The unit is a cd/A. The power efficiency is the current efficiency divided by the operating voltage. The unit is Im/W.

Device Examples 1 -3

These examples illustrate the use of a compound having Formula I as the host material in the photoactive layer of a device. The devices were bottom-emission devices made by thermal evaporation.

Bottom-emission devices were fabricated on patterned indium tin oxide (ITO) coated glass substrates. Cleaned substrates were loaded into a vacuum chamber. Once pressure reached 5 x 10 ^-7 Torr or below, they received thermal evaporations of the hole injection material, a first hole transport material, a second hole transport material, the photoactive and host materials, electron transport materials and electron injection material sequentially. The bottom-emission devices were thermally evaporated with Al cathode material. The chamber was then vented, and the devices were encapsulated using a glass lid, desiccant, and UV curable epoxy.

The device had the structure, in order (unless otherwise specified, all ratios are by weight and all percentages are by weight, based on the total weight of the layer):

Glass substrate

Anode = ITO (50 nm)

HIL = HAT-CN (10 nm)

HTL1 = HTM-1 (165 nm)

HTL2 = HTM-2 (20 nm)

EML = host compound as shown in Table 1 , in a 20:1 weight ratio with Dopant-1 (25 nm)

ETL1 = ET-1 (5 nm)

ETL2 = ET-2:LiQ 1 :1 (22 nm)

EIL = LiQ (3 nm)

Cathode = Al (100 nm)

Table 1. Device results

V10 is the driving voltage at 10 mA/cm ² ; All other data at 1000 nits. CE is the current efficiency in cd/A; CIEx and CIEy are the x and y color coordinates according to the C.I.E. chromaticity scale (Commission Internationale de L'Eclairage, 1931).

Device Examples 4-5

Bottom-emission devices were fabricated on patterned indium tin oxide (ITO) coated glass substrates. Cleaned substrates were loaded into a vacuum chamber. Once pressure reached 5 x 10 ^-7 Torr or below, they received thermal evaporations of the hole injection materials, a first hole transport material, a second hole transport material, the photoactive and host materials, electron transport materials and electron injection material sequentially. The bottom-emission devices were thermally evaporated with Al cathode material. The chamber was then vented, and the devices were encapsulated using a glass lid, desiccant, and UV curable epoxy.

The device had the structure, in order (unless otherwise specified, all ratios are by weight and all percentages are by weight, based on the total weight of the layer):

Glass substrate

Anode: ITO (50 nm)

HIL: HAT-CN (10 nm) \ HTM-4 (90 nm) \ HAT-CN (5 nm)

HTL1 : HTM-1 (72 nm)

HTL2: HTM-3 (10 nm)

EML: host as shown in Table 2, in a 32:1 ratio with Dopant-2 (25 nm)

ETL: ET-2: LiQ 1 :1 (27 nm)

EIL: LiQ (3 nm)

Cathode: Al (100 nm) Table 2. Device results

V10 is the driving voltage at 10 mA/cm ² . All other data at 1000 nits. CIEx and CIEy are the x and y color coordinates according to the C.I.E. chromaticity scale (Commission Internationale de L'Eclairage, 1931). CE is the current efficiency in cd/A.

Note that not all of the activities described above in the

general description or the examples are required, that a portion of a specific activity may not be required, and that one or more further activities may be performed in addition to those described. Still further, the order in which activities are listed are not necessarily the order in which they are performed.

In the foregoing specification, the concepts have been described with reference to specific embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of invention.

Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any feature(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature of any or all the claims.

It is to be appreciated that certain features are, for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. Further, reference to values stated in ranges include each and every value within that range.