Patent ID: 8426041

Claim:
A compound comprising a metal center and a ligand coordinated to the metal center, wherein the ligand is selected from: wherein R 1 and R 2 are independently selected from hydrogen, alkyl, alkenyl, alkynyl, aralkyl, CN, CF 3 , CO 2 R′, C(O)R′, C(O)NR′ 2 , NR′ 2 , NO 2 , OR′, SR', SO 2 , SOR′, SO 3 R′, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; R 3 is selected from hydrogen, alkyl, alkenyl, alkynyl, aralkyl, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; additionally or alternatively, two R groups on the same or adjacent ring, together form a 5 or 6-member cyclic group, wherein said cyclic group is cycloalkyl, cycloheteroalkyl, aryl, or heteroaryl; and wherein said cyclic group is optionally substituted by one or more substituents J; each substituent J is independently selected from the group consisting of R′, CN, CF 3 , C(O)OR′, C(O)R′, C(O)NR′ 2 , NR′ 2 , NO 2 , OR′, SR′, SO 2 , SOR′, or SO 3 R′, and additionally, or alternatively, two J groups on adjacent ring atoms form a fused 5- or 6-membered aromatic group; each R′ is independently selected from H, halo, alkyl, alkenyl, alkynyl, heteroalkyl, aralkyl, aryl, and heteroaryl; a is 0, 1, 2, 3, or 4; and b is 0, 1, 2, or 3.