Luminescent Cu I thiocyanate complexes based on tris(2-pyridyl)phosphine and its oxide: from mono-, di- and trinuclear species to coordination polymers

Tris(2-pyridyl)phosphine oxide reacts with CuSCN to form a variety of luminescent complexes, depending on the specified metal-to-ligand ratio and the solvent used, viz. mononuclear [Cu( N , N ′, N ′′-Py 3 PO)( N CS)], dinuclear ( N , N ′-Py 3 PO)Cu(SCNNCS)Cu[( N , N ′-Py 3 PO)], their co-crystal (2 : 1, correspondingly) and trinuclear {Cu( N CS)[ S CNCu( N , N ′, N ′′-Py 3 PO)] 2 }. In the solid state, these complexes feature red-orange emission upon UV photoexcitation. The reaction of tris(2-pyridyl)phosphine with CuSCN quantitatively produces an almost insoluble coordination polymer, [Cu(Py 3 P)NCS] n , which exhibits bright green emission. The synthesized compounds are the first members of the hitherto unknown family of Cu( i ) thiocyanate complexes supported by tripodal ligands.