Complexes

1. A palladium(II) complex of formula (1):

wherein:

R 1 and R 2 are, independently, substituted or unsubstituted and are straight-chain alkyl, branched-chain alkyl, cycloalkyl, aryl, or heteroaryl, wherein the heteroatoms of the heteroaryl are, independently, sulfur, nitrogen or oxygen, or where the substituted or unsubstituted straight-chain alkyl of R 1 and R 2 are linked to form a ring structure with E;

R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 and R 11 are, independently, H or substituted or unsubstituted groups that are straight-chain alkyl, branched-chain alkyl, cycloalkyl, alkoxy, aryl, heteroaryl, —N(alkyl) 2 wherein the alkyl groups are, independently, straight-chain or branched-chain groups, —N(cycloalkyl) 2 wherein the cycloalkyl groups are the same or different, —N(aryl) 2 wherein the aryl groups are the same or different, —N(heteroaryl) 2 wherein the heteroaryl groups are the same or different, or heterocycloalkyl; or

R 1 /R 3 or R 2 /R 3 forms a ring structure with the atoms to which they are attached and if so, R 4 /R 5 , R 4 /R 6 , R 7 /R 8 , R 8 /R 9 , R 9 /R 10 or R 10 /R 11 may also independently form a ring structure with the carbon atoms to which they are attached;

R 12 is substituted or unsubstituted and is straight-chain alkyl, branched-chain alkyl, cycloalkyl, aryl, or heteroaryl wherein the heteroatoms of the heteroaryl are, independently, sulfur, nitrogen, or oxygen;

m is 0, 1, 2, 3, 4 or 5;

E is P or As; and

X is a coordinating anionic ligand;

wherein:

at least one of R 7 , R 8 , R 9 , R 10 and R 11 is not H; and

when R 8 , R 9 , and R 10 are H, R 7 and R 11 are not OMe.

2. The palladium(II) complex according to claim 1 , wherein E is P.

3. The palladium(II) complex according to claim 2 , wherein R 1 and R 2 are more sterically bulky than a cyclohexyl group when R 7 , R 8 , R 9 , R 10 and/or R 11 are less sterically bulky than a cyclohexyl group.

4. The palladium(II) complex according to claim 2 , wherein R 1 and R 2 are less sterically bulky than a cyclohexyl group when R 7 , R 8 , R 9 , R 10 and/or R 11 are more sterically bulky than a cyclohexyl group.

5. The palladium(II) complex according to claim 1 , wherein R 3 , R 4 , R 5 and R 6 are —H.

6. The palladium(II) complex according to claim 1 , wherein two of R 3 , R 4 , R 5 and R 6 are —H, and the other two of R 3 , R 4 , R 5 and R 6 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, or unsubstituted alkoxy.

7. The palladium(II) complex according to claim 1 , wherein three of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other two of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 , wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 , wherein the aryl groups are the same or different.

8. The palladium(II) complex according to claim 1 , wherein two of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other three of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

9. The palladium(II) complex according to claim 1 , wherein the monodentate tertiary phosphine ligand

is:

10. The palladium(II) complex according to claim 1 , wherein X is a halo group or a trifluoroacetate group.

11. The palladium(II) complex according to claim 1 , wherein the complex of formula (1) is:

12. The palladium(II) complex according to claim 2 , wherein R 3 , R 4 , R 5 and R 6 are —H.

13. The palladium(II) complex according to claim 3 , wherein R 3 , R 4 , R 5 and R 6 are —H.

14. The palladium(II) complex according to claim 4 , wherein R 3 , R 4 , R 5 and R 6 are —H.

15. The palladium(II) complex according to claim 2 , wherein two of R 3 , R 4 , R 5 and R 6 are —H, and the other two of R 3 , R 4 , R 5 and R 6 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, or unsubstituted alkoxy.

16. The palladium(II) complex according to claim 3 , wherein two of R 3 , R 4 , R 5 and R 6 are —H, and the other two of R 3 , R 4 , R 5 and R 6 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, or unsubstituted alkoxy.

17. The palladium(II) complex according to claim 4 , wherein two of R 3 , R 4 , R 5 and R 6 are —H, and the other two of R 3 , R 4 , R 5 and R 6 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, or unsubstituted alkoxy.

18. The palladium(II) complex according to claim 5 , wherein two of R 3 , R 4 , R 5 and R 6 are —H, and the other two of R 3 , R 4 , R 5 and R 6 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, or unsubstituted alkoxy.

19. The palladium(II) complex according to claim 2 , wherein three of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other two of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

20. The palladium(II) complex according to claim 3 , wherein three of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other two of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

21. The palladium(II) complex according to claim 4 , wherein three of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other two of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 , wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 , wherein the aryl groups are the same or different.

22. The palladium(II) complex according to claim 5 , wherein three of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other two of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

23. The palladium(II) complex according to claim 6 , wherein three of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other two of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

24. The palladium(II) complex according to claim 2 , wherein two of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other three of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

25. The palladium(II) complex according to claim 3 , wherein two of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other three of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

26. The palladium(II) complex according to claim 5 , wherein two of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other three of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

27. The palladium(II) complex according to claim 6 , wherein two of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other three of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

28. The palladium(II) complex according to claim 7 , wherein two of R 7 , R 8 , R 9 , R 10 and R 11 are —H, and the other three of R 7 , R 8 , R 9 , R 10 and R 11 are, independently, unsubstituted straight-chain alkyl, unsubstituted branched-chain alkyl, unsubstituted cycloalkyl, unsubstituted alkoxy, unsubstituted —N(alkyl) 2 wherein the alkyl groups are independently straight-chain or branched-chain groups, or unsubstituted —N(aryl) 2 wherein the aryl groups are the same or different.

29. The palladium(II) complex according to claim 2 , wherein X is halo or a trifluoroacetate.

30. The palladium(II) complex according to claim 3 , wherein X is halo or a trifluoroacetate.

31. The palladium(II) complex according to claim 4 , wherein X is halo or a trifluoroacetate.

32. The palladium(II) complex according to claim 5 , wherein X is halo or a trifluoroacetate.

33. The palladium(II) complex according to claim 6 , wherein X is halo or a trifluoroacetate.

34. The palladium(II) complex according to claim 7 , wherein X is halo or trifluoroacetate.

35. The palladium(II) complex according to claim 8 , wherein X is halo or trifluoroacetate.

36. The palladium(II) complex according to claim 9 , wherein X is halo or trifluoroacetate.