Influence of the nitrile group on structure properties of pseudohalogeno-copper(II) and nickel(II) complexes with 3- and 4-cyanopyridines

Abstract

Pseudohalogenocomplexes of the types [CuX2L2] (X = NCO, C(CN)3, N(CN)2; L = 3- or 4-CN-py) and [NiX2L2] (X = C(CN)3, N(CN)2; L as before) have been prepared and investigated by spectroscopic methods. As the results show the [CuX2L2] complexes have pseudooctahedral structures with variable degree of tetragonal distortion and contain bridging pseudohalide ligands. The NCO groups bridge on the end-to-end fashion, forming by their oxygens long axial bondings. The N(CN)2 groups very likely bridge asymmetrically by means of their amide and cyanide nitrogens, the former ones being used for strong equatorial bonds. The [NiX2L2] complexes are octahedral and also exhibit the pseudohalides in bridging function which, however, is realized with dicyanamide symmetrically through both cyanide nitrogens.