STRUCTURAL CHARACTERIZATION OF NITROSODICYANOMETHANIDE AND DICYANAMIDE COMPLEXES OF COPPER(II), NICKEL(II) AND COBALT(II) WITH IMIDAZOLE AND 1-METHYLIMIDAZOLE - X-RAY CRYSTALLOGRAPHIC EVIDENCE OF UNUSUAL NITROSODICYANOMETHANIDE O-BONDING IN CU(ONC(CN)(2))(2) (1-METHYLIMIDAZOLE)(4)

Pseudohalide complexes of the type M{ONC(CN)(2)}(2)L(2), with M = Cu, L = imidazole (iz), 1-methylimidazole (meiz); M = Ni, Co, L = meiz, Cu {ONC(CN)(2)}(2)(meiz)(4) M{ONC(CN)(2)}(2)(iz)(4), with M = Ni, Co, and M{N(CN)(2)}(2)L(2), with M = Cu, Co, L = meiz; M = Ni, L = iz, meiz h ave been prepared and characterized by spectroscopic and magnetic tech niques. The crystal structure of Cu{ONC(CN)(2)}(2)(meiz)(4) has been d etermined by the X-ray diffraction method. The Cu-II environment is el ongated pseudooctahedral, composed of four tertiary meiz nitrogens and two nitrosodicyanomethanide oxygens in longer axial distances. Accord ing to spectroscopic results, the remaining compounds show octahedral (Ni, Co) or pseudooctahedral (Cu) structures, realized in the M:L = 1: 2 and probably also in the 1:4 compounds by bridging pseudohalide func tion. Such bridging is evidenced by magnetic properties of Cu{ONC(CN)( 2)}(2)(meiz)(2), being affected by exchange coupling between the param agnetic metal ions. Copyright (C) 1996 Elsevier Science Ltd