Synthesis of organometallic cyclometallated group viiib metal complexes

1. A process for forming an organometallic cyclometallated Group viiib metal complex comprising reacting a Group viiib metal compound with a heterocyclic compound capable of forming an organometallic cyclometallated complex in the presence of a solvent comprising an aromatic oxygen containing compound.

2. A process according to claim 1 wherein the metal is Pt, Ir, Rh, Pd, Os, or Ru.

3. A process according to claim 1 wherein the metal is Ir(III).

4. A process according to claim 1 wherein aromatic oxygen containing compound is an aromatic ester compound.

5. A process according to claim 1 wherein the aromatic oxygen containing compound is represented by Formula (1a) or Formula (1b):

wherein:

Ar represents an aromatic group; and

R represents a substituent.

6. A process according to claim 5 wherein Ar represents a carbocyclic group and R represents an aliphatic group.

7. A process according to claim 1 wherein aromatic oxygen containing compound is an aromatic ether compound.

8. A process according to claim 1 wherein the aromatic oxygen containing compound is represented by Formula (1c):

wherein:

Ar represents an aromatic group; and

R represents a substituent.

9. A process according to claim 8 wherein Ar represents a carbocyclic group and R represents an aliphatic group.

10. A process according to claim 1 wherein aromatic oxygen containing compound is phenyl acetate or methyl benzoate.

11. A process according to claim 1 wherein the Group viiib metal compound comprises a material represented by the formula M(Y) 6 , wherein M represents a Group viiib metal; and each Y represents an independently selected ligand group.

12. A process according to claim 11 wherein at least one Y represents a halide.

13. A process according to claim 1 wherein the Group viiib metal compound is represented by Formula (2):

(L) 2 M(μ-X) 2 M(L) 2   (2)

wherein:

each L represents an independently selected bidentate cyclometallating ligand;

Each μ-X represents a bridging halide; and

M represents a Group viiib metal.

14. A process according to claim 1 wherein the metal compound is represented by Formula (3):

[(L) 2 M(L 1 ) 2 ] + X −   (3)

wherein:

M represents Ir or Rh;

X − represents an anionic counterion;

each L represents an independently selected bidentate cyclometallating ligand; and

each L 1 represents an independently selected monodentate ligand.

15. A process according to claim 1 wherein the heterocyclic compound comprises a 2-phenylpyridine group.

16. A process according to claim 1 wherein the heterocyclic compound comprise a 3-phenylisoquinoline group.

17. A process according to claim 1 wherein the heterocyclic compound comprise a 1-phenylisoquinoline group.

18. A process according to claim 1 wherein a compound comprising an organometallic bis-cyclometallated complex is formed.

19. A process according to claim 1 wherein a compound comprising an organometallic tris-cyclometallated complex is formed.

20. A process according to claim 1 wherein the cyclometallated metal complex formed comprises a 2-phenylpyridine group.

21. A process according to claim 1 wherein the cyclometallated metal complex formed comprises a 3-phenylisoquinoline group.

22. A process according to claim 1 wherein the cyclometallated metal complex formed comprises a 1 phenylisoquinoline group.

23. A process according to claim 1 wherein organometallic cyclometallated Group viiib metal complex formed is represented by Formula (2):

(L) 2 M(μ-X) 2 M(L) 2   (2)

wherein:

each L represents an independently selected bidentate cyclometallating ligand;

Each μ-X represents a bridging halide; and

M represents a Group viiib metal.

24. A process according to claim 1 wherein organometallic cyclometallated Group viiib metal complex formed is represented by Formula (5):

M(L) 3   (5)

wherein

M represents a Group viiib metal; and

each L represents an independently selected bidentate cyclometallating ligand.

25. A process according to claim 1 comprising two steps, wherein:

a) in the first step a Group viiib metal compound of Formula (1) is reacted with a heterocyclic compound capable of forming an organometallic cyclometallated complex in the presence of a solvent comprising an aromatic oxygen containing compound to form a compound of Formula (2), and

b) in the second step the compound of Formula (2) is further reacted with a heterocyclic compound capable of forming an organometallic cyclometallated complex in the presence of a solvent comprising an aromatic oxygen containing compound to form a compound of Formula (5),

wherein the formulas are

M(Y) 6   (1)

(L) 2 M(μ-X) 2 M(L) 2   (2)

M(L) 3   (5)

in which

M represents a Group viiib metal;

each Y represents a ligand group;

each L represents an independently selected bidentate cyclometallating ligand group; and

Each μ-X represents a bridging halide.

26. A process according to claim 25 wherein both steps are performed in the same reaction vessel.