Patent ID: 8106193

Claim:
A metal-ligand complex comprising a complex of formula I: in which R 1 and R 8 , which may be the same or different, are each a group of formula II; —Z—R 12 II Z is a sigma-bond, —C═C—, —C≡C—, —(CH 2 ) x —, —COO—, —OC(═O)—, —CH═N—, —N═CH—, —C(═O)NH—, —NHC(═O)—, —(CH 2 ) q O—, —O—(CH 2 ) w — or —OC(═O)X 1 R 14 —; R 12 is alkyl C1 to 18 or a group of formula VIII; R 2 , R 3 , R 6 and R 7 , which may be the same or different, are each hydrogen or together the pair of R 2 and R 3 or R 6 and R 7 , form a —(CH 2 ) m — ring; R 4 and R 5 , which may be the same or different, are each hydrogen or halogen; X is a phenate, a thiolate, an acetylide, a phenyl, an alkyl, vinyl, each of which may optionally be substituted by alkyl C1 to 30 or X is a halide; X 1 is C5 or C6 cycloalkyl; Y is hydrogen, hydroxy, halogen, alkyl C1 to 6, haloalkyl C1 to 6, alkoxy C1 to 6, —COOR 13 , cyano or isothiocyanate; R 9 and R 11 , which may be the same or different, are each hydrogen or —OC n H 2n+1 ; R 10 is hydrogen, —OC n H 2y+1 R 13 is hydrogen or alkyl C1 to 18; R 14 is alkyl C1 to 12; m is an integer from 3 to 8; n and y, which may be the same or different, are each an integer from 1 to 30; and x, q and w, which may be the same or different, are each an integer from 1 to 12.