Solvent-resistant hole transport layers

1. A hole transport material having Formula I, Formula Ia, or Formula II:

wherein:

A is selected from the group consisting of formula A-2, formula A-3, and formula A-4

wherein:

Ar 3 , Ar 4 , Ar 4a , Ar 5 and Ar 5a are the same or different and are aryl groups;

L is the same or different at each occurrence and is aryl, (CR′2)q, adamantyl, bicyclic cyclohexyl, or a bicyclic group having aliphatic rings connected through a single atom;

R′ is the same or different at each occurrence and is H, D, alkyl, fluoroalkyl, aryl, deuterated alkyl, deuterated fluoroalkyl, and deuterated aryl;

X is the same or different at each occurrence and is selected from an aryl group, and a deuterated aryl group, with the proviso that N is not bonded directly to G;

n is an integer greater than 0;

n1 is 0 or 1;

q is an integer from 1-5; and

In Formula Ia, G is bonded directly or through a substituent group to one or more of Ar 4 , Ar 4a , Ar 5 , or Ar 5a

wherein:

Ar 6 and Ar 7 are the same or different and are aryl groups;

R 1 through R 5 are independently the same or different at each occurrence and are selected from the group consisting of D, F, alkyl, aryl, alkoxy, silyl, deuterated alkyl, deuterated aryl, deuterated alkoxy, and deuterated silyl;

a through e are independently an integer from 0 to 4;

f is 1 or 2;

g is 0, 1 or 2;

h is 1 or 2; and

In Formula Ia, G is bonded directly or through a substituent group to one or more of Ar 6 , Ar 7 , R 2 , R 3 , R 4 or R 5

wherein:

Ar 8 is the same or different at each occurrence and is selected from the group consisting of phenylene, substituted phenylene, naphthylene, substituted naphthylene, and deuterated analogs thereof;

Ar 9 is the same or different at each occurrence and is an aryl group;

T 1 and T 2 are independently the same or different at each occurrence and are conjugated moieties which are connected in a non-planar configuration;

k is the same or different at each occurrence and is an integer from 1 to 6;

1 is the same or different at each occurrence and is an integer from 1 to 6; and

In Formula Ia, G is bonded directly or through a substituent group to one or more of Ar 8 or Ar 9 ;

B′ is an aromatic moiety;

E is the same or different at each occurrence and is an end group selected from the group consisting of H, D, halide, alkyl, aryl, deuterated alkyl, and deuterated aryl;

G is selected from the group consisting of G1, G2, and deuterated analogs thereof

 where the asterisk represents the point of attachment;

n is an integer greater than 0; and

m1 and m2 represent non-zero mole fractions, such that m1+m2=1.

2. The hole transport material of claim 1 having Formula I.

3. The hole transport material of claim 1 having Formula Ia.

4. The hole transport material of claim 1 having Formula II.

5. The hole transport material of claim 1 , wherein G is selected from the group consisting of G1-a, G1-b, G1-c, G1-d, and mixtures thereof

6. The hole transport material of claim 5 , wherein G is selected from the group consisting of G1-b, G1-c, and mixtures thereof.

7. The hole transport material of claim 1 , wherein G is selected from the group consisting of G2-a, G2-b, and mixtures thereof

8. The hole transport material of claim 7 , wherein G is G2-b.

9. A hole transport material having Formula Ia or Formula II:

wherein:

A has formula A-1

wherein:

Ar 1 -Ar 2 are the same or different and are aryl groups; and

X is the same or different at each occurrence and is selected from an aryl group, and a deuterated aryl group, with the proviso that N is not bonded directly to G; and

in Formula Ia, G is bonded directly or through a substituent group to Ar 2 ;

B′ is an aromatic moiety;

E is the same or different at each occurrence and is an end group selected from the group consisting of H, D, alkyl, aryl, deuterated alkyl, and deuterated aryl;

G is selected from the group consisting of G1, G2, and deuterated analogs thereof

 where the asterisk represents the point of attachment;

n is an integer greater than 0; and

m1 and m2 represent non-zero mole fractions, such that m1+m2=1.

10. The hole transport material of claim 1 , wherein B′ has formula B-1

wherein:

Ar 1 -Ar 2 are the same or different and are aryl groups; and

X is the same or different at each occurrence and is selected from a single bond, an aryl group, and a deuterated aryl group.

11. The hole transport material of claim 1 , wherein B′ has formula B-2

wherein:

Ar 3 -Ar 5 are the same or different and are aryl groups;

L is the same or different at each occurrence and is aryl, (CR′2)q, adamantyl, bicyclic cyclohexyl, or a bicyclic group having aliphatic rings connected through a single atom;

R′ is the same or different at each occurrence and is H, D, alkyl, fluoroalkyl, aryl, deuterated alkyl, deuterated fluoroalkyl, and deuterated aryl;

X is the same or different at each occurrence and is selected from a single bond, an aryl group, and a deuterated aryl group;

p is the same or different at each occurrence and is 0 or 1, with the proviso that at least one p=1; and

q is an integer from 1-5.

12. The hole transport material of claim 1 , wherein B′ has formula B-3

wherein:

Ar 6 and Ar 7 are the same or different and are aryl groups;

R 1 through R 5 are independently the same or different at each occurrence and are selected from the group consisting of D, F, alkyl, aryl, alkoxy, silyl, deuterated alkyl, deuterated aryl, deuterated alkoxy, and deuterated silyl;

a through e are independently an integer from 0 to 4;

f is 1 or 2;

g is 0, 1 or 2; h is 1 or 2; and

p is the same or different at each occurrence and is 0 or 1, with the proviso that at least one p=1.

13. The hole transport material of claim 1 , wherein B′ has formula B-4

wherein:

Ar 8 is the same or different at each occurrence and is selected from the group consisting of phenylene, substituted phenylene, naphthylene, substituted naphthylene, and deuterated analogs thereof;

Ar 9 is the same or different at each occurrence and is an aryl group;

T 1 and T 2 are independently the same or different at each occurrence and are conjugated moieties which are connected in a non-planar configuration;

k is the same or different at each occurrence and is an integer from 1 to 6; and

p is the same or different at each occurrence, with the proviso that at least one p=1.

14. A hole transport material having Formula I:

wherein:

A is formula A-1

wherein:

Ar 1 -Ar 2 are the same or different and are aryl groups;

X is the same or different at each occurrence and is selected from an aryl group, and a deuterated aryl group, with the proviso that N is not bonded directly to G; and

G is selected from the group consisting of G1, G2, and deuterated analogs thereof

 where the asterisk represents the point of attachment;

n is an integer greater than 2; and

m1 and m2 represent non-zero mole fractions, such that m1+m2=1.

15. The hole transport material of claim 1 , wherein the hole transport material is selected from the group consisting of following compounds: