Transition metal complexes and use thereof in organic light-emitting diodes V

1. A metal complex, comprising a ligand of formula (I):

wherein:

Y 5 is CD, CR 1 , CH, or N;

D is deuterium;

X 1 is N

X 2 , X 3 , Y 1 , Y 2 , and Y 3 are each independently N or C;

X 4 is CD, CR 1 , CH, N, NR 1 , S or O;

X 5 is CD,

Y 4 and Y 6 are each independently CD, CR 1 , CH, N, NR 1 , S, or O;

Z 1 , Z 2 , and Z 3 are each independently CD, CR 1 , CH, N, S, O, or NR 1 ;

R 1 is independently an unsubstituted or substituted alkyl, unsubstituted or substituted cycloalkyl, unsubstituted or substituted heterocycloalkyl, unsubstituted or substituted aryl, unsubstituted or substituted heteroaryl, unsubstituted or substituted alkenyl, unsubstituted or substituted cycloalkenyl, unsubstituted or substituted alkynyl, SiR 2 3 , halogen, a substituent with donor or acceptor action, whereby, in the case that R 1 is bonded to a nitrogen atom, R 1 is independently an unsubstituted or substituted alkyl, unsubstituted or substituted aryl, or unsubstituted or substituted heteroaryl, whereby any two R 1 radicals together may additionally form an alkylene or arylene bridge;

R 2 is independently an unsubstituted or substituted alkyl, unsubstituted or substituted aryl, or unsubstituted or substituted heteroaryl;

m is 1;

n is 0;

Z 4 is absent;

the metal complex comprises a deuterium atom; and

a metal of the metal complex is Ir(III), Pt(II), or Os(II).

2. The metal complex according to claim 1 , wherein at least one of X 4 , Y 4 , Y 5 , Y 6 , Z 1 , Z 2 , and Z 3 is CD.

3. The metal complex according to claim 1 , wherein X 1 and Y 1 are N.

4. The metal complex according to claim 1 , wherein

X 1 is N;

X 2 , Y 1 , Y 2 , and Y 3 , are each C;

X 3 is C or N;

X 4 is CR 1 , CD, N, NR 1 , O, or S;

Y 4 , Y 5 , and Y 6 are each independently CH, CD or CR 1 ;

Z 1 , Z 2 , and Z 3 are each independently CH, CD, CR 1 , N, S, O, or NR 1 .

5. The metal complex according to claim 3 , wherein

X 1 is N, and

X 4 is CD or CR 1 .

6. The metal complex according to claim 5 , wherein

X 3 is N,

X 4 and Z 3 are each CR 1 , and

Y 4 , Y 5 , Y 6 , Z 1 , and Z 2 are each CD.

7. The metal complex according to claim 1 , wherein

R 1 is independently an unsubstituted or substituted alkyl, unsubstituted or substituted aryl, unsubstituted or substituted heteroaryl, SiR 2 3 , F, OR 2 , SR 2 , NR 2 2 , CF 3 , or CN, whereby each R 1 , in the case that R 1 is bonded to a nitrogen atom, is independently an unsubstituted or substituted alkyl or unsubstituted or substituted aryl; and

R 2 is independently an unsubstituted or substituted alkyl or unsubstituted or substituted aryl.

8. The metal complex according to claim 1 , wherein the metal complex has formula (II):

wherein:

M is Ir(III), Pt(II), or Os(II);

J is a mono- or dianionic ligand which is optionally mono- or bidentate;

K is an uncharged, mono- or bidentate ligand which is optionally photoactive;

o is 1, 2, 3, or 4, whereby o is 1, 2, or 3 when M is Ir(III), and is 1 or 2 when M is Pt(II) or Os(II);

p is 0, 1, 2, 3, or 4, whereby p is 0, 1, 2, 3, or 4 when M is Ir(III), and is 0, 1 or 2 when M is Pt(II) and Os(II), and p is a number of bonding sites to the metal atom M;

q is 0, 1, 2, 3, or 4, whereby q is 0, 1, or 2 when M is Ir(III), is 0 or 1 when M is Pt(II), and is 2 or 3 when M is Os(II), and q is a number of bonding sites to the metal atom M; and

wherein o, p, and q depend on the oxidation state and coordination number of the metal atom present and on charge of the ligands.

9. The metal complex according to claim 8 , wherein the metal complex has formula (IIa)

wherein:

M is Ir(III) or Pt(II);

 is a bidentate monoanionic ligand which optionally comprises a deuterium atom;

p′ is 0, 1, or 2, whereby p′ is 0, 1, or 2 when M is Ir(III), and is 0 or 1 when M is Pt(II), wherein p′ is a number of

ligands;

a sum of o+p′ is 3 when M is Ir(III);

the sum of o+p′ is 2 when M is Pt(II); and

o is at least 1.

10. The metal complex according to claim 9 , wherein L in the bidentate monoanionic ligand is in each case independently selected the group consisting of from O, N, and C.

11. An organic light-emitting diode, comprising the metal complex according to claim 1 .

12. A light-emitting layer, comprising the metal complex according to claim 1 .

13. An organic light-emitting diode, comprising the light-emitting layer according to claim 12 .

14. A device, selected from the group consisting of a stationary visual display unit, an illumination and a mobile visual display unit, comprising the organic light-emitting diode according to claim 11 .

15. A device, selected from the group consisting of a stationary visual display unit, an illumination, and mobile visual display unit, comprising the organic light-emitting diode according to claim 13 .