Patent ID: 7345172

Claim:
A compound, comprising a cationic moiety of the formula: M(R 1 )(R 2 )(R 3 ) 3+ wherein: M is a metal selected from a group consisting of Rh, Ru, Co, Fe, Cr, Cu, Zn, Cd, and Pb, each of R 1 and R 2 is a ligand independently selected from a group consisting of ethylenediamine or a substituted derivative thereof, and an aryl or heteroaryl comprising 1 to 5 rings; and R 3 is a ligand having the following structure: wherein: each of R 4 and R 5 is independently selected from a group consisting of —H and a lower alkyl, R 6 and R 7 are taken together to form a substituted or an unsubstituted fused heteroaryl ring system comprising at least four rings, wherein each ring contains from 0 to 2 heteroatoms, and wherein the substituents in the substituted ring system are selected from a group consisting of —H, —R, halo, —OH, —OR, —NH 2 , —NHR, —NR 2 , —CN, —NO 2 , —SH, —SO 3 , —OSO 3 , —C(O)OH, —C(O)OR, —C(O)NH 2 , —C(O)NHR, —C(O)NR 2 , —SO 3 R, and —OSO 3 R, wherein each R is independently selected from a group consisting of a lower alkyl, a cycloalkyl, a lower alkenyl, a lower alkynyl, and phenyl, with the further proviso that in the fused heteroaryl ring system, at least one ring contains 1 or 2 heteroatoms.