Iridium complex compound, solution composition containing the compound, organic electroluminescent element, display, and lighting

1. An iridium complex compound represented by the following formula (1):

in the formula (1), the ring A represents a 6-membered or 5-membered aromatic hydrocarbon ring, containing the carbon atoms C 1 and C 2 or a 6-membered or 5-membered heteroaromatic ring containing the carbon atoms C 1 and C 2 , the ring B represents a 6-membered or 5-membered nitrogen-containing heteroaromatic ring containing the carbon atom C 3 and the nitrogen atom N 1 ; L represents an organic ligand; a and b each independently indicate an integer of from 1 to 4; n indicates an integer of from 1 to 3;

R 1 and R 2 each represent a substituent bonding to ring A and ring B, respectively, multiple R 1 s and R 2 s each are the same or different, and R 1 and R 2 represents a structure of formula (2) or any of a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, or a (hetero)aryl group having from 3 to 20 carbon atoms; these groups are optionally substituted with an atom or group selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, and a (hetero)aryl group having from 3 to 20 carbon atoms;

when a is 2 or more and multiple R's neighbor to each other, then the neighboring R 1 s may bond directly, or may bond via an alkylene group having from 3 to 12 carbon atoms, an alkenylene group having from 3 to 12 carbon atoms, or an arylene group having from 6 to 12 carbon atoms thereby to further form a ring; when b is 2 or more and multiple R 2 s neighbor to each other, then the neighboring R 2 s may bond directly, or may bond via an alkylene group having from 3 to 12 carbon atoms, an alkenylene group having from 3 to 12 carbon atoms, or an arylene group having from 6 to 12 carbon atoms thereby to further form a ring; R 1 and R 2 may bond directly, or may bond via an alkylene group having from 3 to 12 carbon atoms, an alkenylene group having from 3 to 12 carbon atoms, or an arylene group having from 6 to 12 carbon atoms thereby to further form a ring; the ring formed by bonding of R 1 s, R 2 s or R 1 and R 2 is optionally substituted with a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkyl amino group having from 2 to 20 carbon atoms, a (hetero)aryl amino group having from 3 to 20 carbon atoms, or a (hetero)aryl group having from 3 to 20 carbon atoms;

provided that at least one of R 1 is represented by the structure of formula (2):

in the formula (2), multiple Xs are the same or different, and X represents a (hetero)arylene group having from 6 to 20 carbon atoms, multiple Ar 1 s are the same or different, and Ar 1 represents a (hetero)aryl group having from 3 to 20 carbon atoms; wherein these groups are optionally substituted with an atom or group selected from the group consisting of a fluorine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, and a (hetero)aryl group having from 3 to 20 carbon atoms; Z is represented by the following formula (3); c indicates an integer of 1; d indicates an integer of from 1 to 3:

in the formula (3), multiple R's are the same or different, and R′ represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, or a (hetero)aryl group having from 3 to 20 carbon atoms; r indicates an integer of from 2 to 20.

2. The iridium complex compound according to claim 1 , wherein in the formula (1), at least one of the substituents R 2 s bonding to the ring B is represented by the formula (2).

3. The iridium complex compound according to claim 1 , wherein in the formula (1), the ring A is a benzene ring or a pyridine ring.

4. The iridium complex compound according to claim 1 , which is represented by the following formula (1-1):

in the formula (1-1), the ring B, R 2 , L, b and n each have the same meanings as in the formula (1);

R 3 to R 6 each are the same or different, and represent a structure of formula (2) or any of a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, or a (hetero)aryl group having from 3 to 20 carbon atoms; wherein these groups are optionally substituted with an atom or group selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, and a (hetero)aryl group having from 3 to 20 carbon atoms;

regarding R 3 to R 6 , the neighboring R 3 s to R 6 s may bond directly, or may bond via an alkylene group having from 3 to 12 carbon atoms, an alkenylene group having from 3 to 12 carbon atoms, or an arylene group having from 6 to 12 carbon atoms thereby to form a ring; wherein these rings are optionally substituted with an atom or group selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkyl silyl group having from 1 to 20 carbon atoms, a (hetero)aryl silyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, and a (hetero)aryl group having from 3 to 20 carbon atoms;

provided that the iridium complex compound represented by the formula (1-1) has at least one group represented by the formula (2) at R 3 to R 6 .

5. The iridium complex compound according to claim 4 , wherein R 4 is represented by the formula (2).

6. The iridium complex compound according to claim 4 , wherein R 5 is represented by the formula (2).

7. The iridium complex compound according to claim 1 , wherein the ring B is a pyridine ring, a pyrazine ring, a pyrimidine ring, an imidazole ring, an oxazole ring or a thiazole ring.

8. The iridium complex compound according to claim 1 , wherein the ring B is a pyridine ring.

9. The iridium complex compound according to claim 1 , wherein the ring B is a pyrazine ring.

10. The iridium complex compound according to claim 1 , wherein the ring B is a pyrimidine ring.

11. The iridium complex compound according to claim 1 , wherein the ring B is an imidazole ring.

12. The iridium complex compound according to claim 1 , wherein in the formula (2), Ar 1 is an aromatic hydrocarbon group having from 6 to 20 carbon atoms.

13. A light-emitting material comprising the iridium complex compound according to claim 1 .

14. A composition comprising the iridium complex compound according to claim 1 and a solvent.

15. An organic electroluminescent element comprising an anode, a cathode and at least one organic layer between the anode and the cathode, wherein at least one layer of the organic layers is a layer formed using the composition according to claim 14 .

16. An organic electroluminescent element comprising an anode, a cathode and at least one organic layer between the anode and the cathode, wherein at least one layer of the organic layers contains the iridium complex compound according to claim 1 .

17. The organic electroluminescent element according to claim 16 , wherein the organic layer further contains a nitrogen-containing aromatic heterocyclic compound as a charge transport material.

18. A display using the electroluminescent element according to claim 16 .

19. A lighting using the electroluminescent element according to claim 16 .

20. An iridium complex compound represented by the following formula (1):

in the formula (1), the ring A represents a 6-membered or 5-membered aromatic hydrocarbon ring, containing the carbon atoms C 1 and C 2 or a 6-membered or 5-membered heteroaromatic ring containing the carbon atoms C 1 and C 2 , the ring B represents a 6-membered or 5-membered nitrogen-containing heteroaromatic ring containing the carbon atom C 3 and the nitrogen atom N 1 ; L represents an organic ligand; a and b each independently indicate an integer of from 1 to 4; n indicates an integer of from 1 to 3;

R 1 and R 2 each represent a substituent bonding to ring A and ring B, respectively, multiple R 1 s and R 2 s each are the same or different, and R 1 and R 2 represents a structure of formula (2) or any of a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, or a (hetero)aryl group having from 3 to 20 carbon atoms; these groups are optionally substituted with an atom or group selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, and a (hetero)aryl group having from 3 to 20 carbon atoms;

when a is 2 or more and multiple R 1 s neighbor to each other, then the neighboring R 1 s may bond directly, or may bond via an alkylene group having from 3 to 12 carbon atoms, an alkenylene group having from 3 to 12 carbon atoms, or an arylene group having from 6 to 12 carbon atoms thereby to further form a ring; when b is 2 or more and multiple R 2 s neighbor to each other, then the neighboring R 2 s may bond directly, or may bond via an alkylene group having from 3 to 12 carbon atoms, an alkenylene group having from 3 to 12 carbon atoms, or an arylene group having from 6 to 12 carbon atoms thereby to further form a ring; R 1 and R 2 may bond directly, or may bond via an alkylene group having from 3 to 12 carbon atoms, an alkenylene group having from 3 to 12 carbon atoms, or an arylene group having from 6 to 12 carbon atoms thereby to further form a ring; the ring formed by bonding of R 1 s, R 2 s or R 1 and R 2 is optionally substituted with a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, a (hetero)aralkyl group having from 7 to 40 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkylsilyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, or a (hetero)aryl group having from 3 to 20 carbon atoms;

provided that at least one of R 1 is represented by the structure of formula (2):

in the formula (2), multiple Xs are the same or different, and X represents a (hetero)arylene group having from 6 to 20 carbon atoms, multiple Ar 1 s are the same or different, and Ar 1 represents a (hetero)aryl group having from 3 to 20 carbon atoms; wherein these groups are optionally substituted with an atom or group selected from the group consisting of a fluorine atom, an alkyl group having from 1 to 20 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, an alkyl silyl group having from 1 to 20 carbon atoms, a (hetero)arylsilyl group having from 3 to 20 carbon atoms, an alkylcarbonyl group having from 2 to 20 carbon atoms, a (hetero)arylcarbonyl group having from 4 to 20 carbon atoms, an alkylamino group having from 2 to 20 carbon atoms, a (hetero)arylamino group having from 3 to 20 carbon atoms, and a (hetero)aryl group having from 3 to 20 carbon atoms; Z is represented by the following formula (3); c indicates an integer of 1; d indicates an integer of from 1 to 3:

in the formula (3), multiple R's are the same or different, and R′ represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an alkyl group having from 1 to 20 carbon atoms, an alkoxy group having from 1 to 20 carbon atoms, a (hetero)aryloxy group having from 3 to 20 carbon atoms, or a (hetero)aryl group having from 3 to 20 carbon atoms; r indicates an integer of from 1 to 20.