Copper coordination compounds of chelating imidazole-azo-aryl ligand. The molecular structures of bis[1-ethyl-2-(p-tolylazo)imidazole]-bis-(azido)copper(ii) and bis[1-methyl-2-(phenylazo)imidazole]-bis(thiocyanato)copper(ii)

Abstract

Reaction of Cu(ClO4)2 6H2O with 1-alkyl-2-(arylazo)imidazole [RaaiR′ where R = H (a), Me (b); R′ = Me (1), Et (2)] and NaN3/NH4SCN (1 ∶ 2 ∶ 2 mole ratio) form mononuclear complexes [Cu(RaaiR′)2(N3)2] (3,4) and [Cu(RaaiR′)2(SCN)2]. DMF (5,6). The complexes are characterized by elemental, spectral, electrochemical and other physicochemical results. The structures of both the complexes are confirmed by the single crystal X-ray diffraction studies of [Cu(MeaaiEt)2(N3)2] (4b) and [Cu(HaaiMe)2(SCN)2]. DMF (5a). The complexes are reduced to [Cu(RaaiR′)2]+ by ascorbic acid. However, air oxidation of [Cu(MeaaiEt)2](ClO4) in presence of N3−/SCN− produces [Cu(MeaaiEt)2(N3/NCS)2].