Metal complexes comprising azabenzimidazole carbene ligands and the use thereof in OLEDs

1. A metal-carbene complex of formula (I):

wherein:

M is Ir;

n is an integer selected from 1, 2 and 3, where the ligand(s):

are each bidentate ligands;

Y is NR 1 ;

R 1 is ethyl, isopropyl, tert-butyl, neopentyl, CF 3 , a substituted or unsubstituted cycloalkyl radical having 5 to 20 carbon atoms, or a substituted or unsubstituted aryl radical having 6 to 30 carbon atoms;

R 2 , R 3 , R 4 are each independently hydrogen, a linear or branched alkyl radical having 1 to 6 carbon atoms, substituted or unsubstituted aryl radical having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action selected from halogen radicals; CF 3 , CN and SiMe 3 , or

R 2 and R 3 or R 3 and R 4 form, together with the carbon atoms to which they are bonded, an optionally substituted unsaturated, saturated or aromatic ring which is optionally interrupted by at least one further heteroatom, has a total of 5 to 18 carbon atoms and/or heteroatoms and may optionally be fused to at least one further optionally substituted saturated or unsaturated or aromatic ring optionally interrupted by at least one further heteroatom and having a total of 5 to 18 carbon atoms and/or heteroatoms;

A 1 is CR 6 ;

A 2 is CR 7 ;

A 3 is CR 8 ;

A 4 is CR 9 ;

R 6 , R 7 , R 8 , R 9 are each independently hydrogen, a linear or branched alkyl radical optionally bearing at least one functional group, optionally interrupted by at least one heteroatom and having 1 to 20 carbon atoms, substituted or unsubstituted aryl radical having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action selected from halogen radicals, CF 3 , CN and SiMe 3 , or

R 6 and R 7 , R 7 and R 8 , or R 8 and R 9 form, together with the carbon atoms to which they are bonded, a saturated, unsaturated or aromatic, optionally substituted ring which is optionally interrupted by at least one heteroatom, has a total of 5 to 18 carbon atoms and/or heteroatoms and may optionally be fused to at least one further optionally substituted saturated or unsaturated or aromatic ring optionally interrupted by at least one further heteroatom and having a total of 5 to 18 carbon atoms and/or heteroatoms;

p is 1;

K is an uncharged mono- or bidentate ligand;

L is a carbene ligand of formula (II):

a ligand of the formula (B):

picolinato,

salicylato,

8-hydroxyquinolato, or

a heterocyclic noncarbene ligand of formula (III):

A 9 is CR 12 or N;

A 10 is CR 13 or N;

R 11 is a linear or branched alkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms, substituted or unsubstituted heterocycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms and/or heteroatoms, substituted or unsubstituted aryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having a total of 5 to 18 carbon atoms and/or heteroatoms;

R 12 , R 13 are each independently hydrogen, a linear or branched alkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms, substituted or unsubstituted heterocycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms and/or heteroatoms, substituted or unsubstituted aryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action;

A 5 is CR 14 or N;

A 6 is CR 15 or N;

A 7 is CR 16 or N;

A 8 is CR 17 or N;

R 14 , R 15 , R 16 , R 17 are each independently hydrogen, a linear or branched alkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms, substituted or unsubstituted heterocycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms and/or heteroatoms, substituted or unsubstituted aryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action, or

R 14 and R 15 , R 15 and R 16 or R 16 and R 17 form, together with the carbon atoms to which they are bonded, an unsaturated or aromatic, optionally substituted ring optionally interrupted by at least one heteroatom and having a total of 5 to 18 carbon atoms and/or heteroatoms, and/or

R 12 and R 13 form, together with A 9 and A 10 to which they are bonded, an unsaturated or aromatic, optionally substituted ring optionally interrupted by exactly one heteroatom or two adjacent heteroatoms and having a total of 5 to 18 ring atoms, and/or

if A 9 is CR 12 , R 12 and R 17 together form a saturated or unsaturated, linear or branched bridge optionally comprising heteroatoms, aromatic units, heteroaromatic units and/or functional groups and having a total of 1 to 30 carbon atoms and/or heteroatoms, to which is optionally fused a substituted or unsubstituted, five- to eight-membered ring comprising carbon atoms and/or heteroatoms;

q is 0 or 1;

R 51 is in each case independently a linear or branched alkyl radical having 1 to 6 carbons atoms, substituted or unsubstituted aryl radical having 6 to 20 carbon atoms; substituted or unsubstituted heteroaryl radical having a total of 5 to 18 carbon atoms and/or heteroatoms;

R 52 is hydrogen, a linear or branched alkyl radical having 1 to 6 carbon atoms, substituted or unsubstituted aryl radical having 6 to 20 carbon atoms;

D are each independently CR 18 or N;

W is C, N;

E are each independently CR 19 , N, NR 20 ;

G is CR 21 , N, NR 22 , S, or O;

R 18 , R 19 , R 21 are each independently hydrogen, a linear or branched alkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms, substituted or unsubstituted heterocycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms and/or heteroatoms, substituted or unsubstituted aryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action, or

in each case 2 R 18 , R 19 and R 21 radicals, together with the carbon atoms to which they are bonded, form a saturated, unsaturated or aromatic, optionally substituted ring optionally interrupted by at least one heteroatom and having a total of 5 to 18 carbon atoms and/or heteroatoms;

R 20 , R 22 are each independently a linear or branched alkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms, substituted or unsubstituted heterocycloalkyl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 3 to 20 carbon atoms and/or heteroatoms, substituted or unsubstituted aryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical optionally interrupted by at least one heteroatom, optionally bearing at least one functional group and having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action; preferably o,o′-dialkylated aryl radical;

where the solid curved line is an optional bridge between one of the D groups and the G group, and the bridge is defined as alkylene, arylene, heteroarylene, alkynylene, alkenylene, NR 23 , O, S, SiR 24 R 25 , CR 50 ═N and (CR 26 R 27 ) d , where one or more nonadjacent (CR 26 R 27 ) groups may be replaced by NR 23 , O, S, SiR 24 R 25 ;

d is 2 to 10;

R 24 , R 25 , R 26 , R 27 , R 50 are each H, alkyl, aryl, heteroaryl, alkenyl, alkynyl;

m is 0, 1 or 2, where, when m is 2, the K ligands may be the same or different; and

o is 0, 1 or 2, where, when o is 2, the L ligands may be the same or different,

wherein the following compounds are excluded:

2. The metal-carbene complex according to claim 1 , wherein:

n is 3, where the ligands

are each bidentate ligands, where all n ligands are the same; and

m, o are each 0.

3. The metal-carbene complex according to claim 1 , wherein:

n is 1, 2 or 3, where the ligand(s)

are each bidentate ligands;

R 1 is ethyl, isopropyl, tert-butyl, neopentyl, CF 3 , a substituted or unsubstituted cycloalkyl radical having 5 to 20 carbon atoms, substituted or unsubstituted aryl radical having 6 to 30 carbon atoms;

R 2 , R 3 , R 4 are each independently hydrogen, a linear or branched alkyl radical having 1 to 6 carbon atoms, substituted or unsubstituted aryl radical having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action selected from halogen radicals; CF 3 , CN and SiMe 3 ; or

R 2 and R 3 or R 3 and R 4 form, together with the carbon atoms to which they are bonded, an optionally substituted unsaturated, saturated or aromatic ring which is optionally interrupted by at least one further heteroatom, has a total of 5 to 18 carbon atoms and/or heteroatoms and may optionally be fused to at least one further optionally substituted saturated or unsaturated or aromatic ring optionally interrupted by at least one further heteroatom and having a total of 5 to 18 carbon atoms and/or heteroatoms;

R 6 , R 7 , R 8 , R 9 are each independently hydrogen, a linear or branched alkyl radical optionally bearing at least one functional group, optionally interrupted by at least one heteroatom and having 1 to 20 carbon atoms, substituted or unsubstituted aryl radical having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl radical having a total of 5 to 18 carbon atoms and/or heteroatoms, group with donor or acceptor action selected from halogen radicals, CF 3 , CN and SiMe 3 , or

R 6 and R 7 , R 7 and R 8 , or R 8 and R 9 form, together with the carbon atoms to which they are bonded, a saturated, unsaturated or aromatic, optionally substituted ring which is optionally interrupted by at least one heteroatom, has a total of 5 to 18 carbon atoms and/or heteroatoms and may optionally be fused to at least one further optionally substituted saturated or unsaturated or aromatic ring optionally interrupted by at least one further heteroatom and having a total of 5 to 18 carbon atoms and/or heteroatoms;

m is 0; and

o is 0, 1 or 2.

4. The metal-carbene complex according to claim 1 , wherein:

n is 3, where the ligand(s)

are each bidentate ligands.

5. A process for preparing the metal-carbene complex of claim 1 , the process comprising contacting at least one compound comprising the metal M with compounds of the general formula (IV) or (V):

to form the metal-carbene complex,

wherein:

R 28 is independently SiR 29 R 30 R 31 , aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl;

X is F, Cl, Br, I, PF 6 , BF 4 ; and

R 29 , R 30 , R 31 are each independently aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl.

6. An organic electronic component comprising at least one metal-carbene complex according to claim 1 .

7. The organic electronic component according to claim 6 , wherein the organic electronic component is selected from organic light-emitting diodes (OLEDs), organic photovoltaic cells (OPVs), organic field-effect transistors (OFETs) and light-emitting electrochemical cells (LEECs).

8. The organic electronic component according to claim 7 , wherein the organic electronic component is an OLED comprising a light-emitting layer comprising the metal-carbene complex.

9. The organic electronic component according to claim 7 , wherein the organic electronic component is an OLED comprising the metal-carbene complex and at least one compound of the formula (X):

wherein:

T is NR 57 , S, O or PR 57 ;

R 57 is aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl;

Q′ is —NR 58 R 59 , —SiR 70 R 71 R 72 , —P(O)R 60 R 61 , —PR 62 R 63 , —S(O) 2 R 64 , —S(O)R 65 , —SR 66 or —OR 67 ;

R 55 , R 56 are each independently alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, SiR 70 R 71 R 72 , a Q′ group or a group with donor or acceptor action;

a″ is 0, 1, 2, 3 or 4;

b′ is 0, 1, 2 or 3;

R 58 ,R 59 form, together with the nitrogen atom, a cyclic radical which has 3 to 10 ring atoms and may be unsubstituted or substituted by one or more substituents selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl and a group with donor or acceptor action, and/or may be fused to one or more further cyclic radicals having 3 to 10 ring atoms, where the fused radicals may be unsubstituted or substituted by one or more substituents selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl and a group with donor or acceptor action; and

R 70 , R 71 , R 72 , R 60 , R 61 , R 62 , R 63 , R 64 , R 65 , R 66 , R 67 are each independently aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl, or

two units of the general formula (X) are optionally bridged to one another via a linear or branched, saturated or unsaturated bridge optionally interrupted by at least one heteroatom, via a bond or via O.

10. The organic electronic component according to claim 9 , comprising at least one compound of the formula (XI) or (XI*):

wherein:

T is NR 57 , S, O or PR 57 ;

R 57 is aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl;

Q is —NR 58 R 59 , —SiR 70 R 71 R 72 , —P(O)R 60 R 61 , —PR 62 R 63 , —S(O) 2 R 64 , —S(O)R 65 , —SR 66 or —R 67 ;

R 70 , R 71 , R 72 are each independently aryl, heteroaryl, alkyl, cycloalkyl, heterocycloalkyl or OR 73 ;

R 55 , R 56 are each independently alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, a Q group or a group with donor or acceptor action;

a′, b′ for the compound of the formula (XI): are each independently 0, 1, 2, 3; for the compound of the formula (XI*), a′ is 0, 1, 2 and b′ is 0, 1, 2, 3, 4;

R 58 , R 59 form, together with the nitrogen atom, a cyclic radical which has 3 to 10 ring atoms and may be unsubstituted or substituted by one or more substituents selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl and a group with donor or acceptor action and/or may be fused to one or more further cyclic radicals having 3 to 10 ring atoms, where the fused radicals may be unsubstituted or substituted by one or more substituents selected from alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl and a group with donor or acceptor action;

R 73 are each independently SiR 74 R 75 R 76 , aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl, optionally substituted by an OR 77 group;

R 77 are each independently SiR 74 R 75 R 76 , aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl; and

R 60 , R 61 , R 62 , R 63 , R 64 , R 65 , R 66 , R 67 , R 74 , R 75 , R 76 are each independently aryl, heteroaryl, alkyl, cycloalkyl or heterocycloalkyl, or

two units of the general formulae (XI) and/or (XI*) are optionally bridged to one another via a linear or branched, saturated or unsaturated bridge optionally interrupted by at least one heteroatom or via O, where this bridge in the general formulae (XI) and/or (XI*) is in each case attached to the silicon atoms in place of R 71 .

11. The organic electronic component according to claim 10 , wherein the organic electronic component is an OLED comprising an emission layer comprising the metal-carbene complex and at least one matrix material of the formula (X) and/or (XI) or (XI*).

12. The organic electronic component according to claim 8 , wherein the organic electronic component is an OLED comprising an emission layer consisting of the metal-carbene complex.

13. A device selected from the group consisting of a stationary visual display unit, a mobile visual display unit, and an illuminator, comprising at least one OLED according to claim 7 .

14. An OLED, comprising the metal-carbene complex according to claim 1 .

15. The OLED according to claim 14 , wherein the metal-carbene complex is adapted to function as an emitter, matrix material, charge transport material, charge blocker, or a combination thereof.

16. An OLED, comprising the metal-carbene complex according to claim 1 , wherein the metal-carbene complex is adapted to function as a hole transport material, a charge blocker, or both.