Different bonding modes for 6-(2-thienyl)-2,2′-bipyridine at ruthenium ( II ); the structural characterisation of [Ru(HL)(HL)Cl][BF 4 ][HL=6-(2-thienyl)-2,2′-bipyridine]

The ligand 6-(2-thienyl)-2,2′-bipyridine (HL) forms ruthenium complexes in which it acts as a terdentate N,N,S-donor, a bidentate N,N-donor, and in a deprotonated form a terdentate N,N,C-donor; the complex [RuCl(HL)2][BF4] has been structurally characterised and shown to contain both N,N,S-- and N,N-bonded ligands.