Reactions of bis(isoproplxanthato)nickel(II) with nitrogen or oxygen donor ligands—III. X-ray crystal structure of the complex with pyrazine

Abstract

Reactions of [Ni(Pr ixa 2] (Pr ixa = i-C 3H 7OCS 2 −) with nitrogen pyr = 1,4-pyrazine, N, N-deen = N, N-diethylethylenediamine, N, N′-deen = N, N′-diethylethylenediamine or teen = N, N, N′, N′-tetraethylethylenediamine) or oxygen (dmso = dimethyl sulfoxide) donor ligands resulted in the formation of the following compounds : [Ni(Pr ixa) 2(pyr)] n , [Ni(Pr ixa) 2( N, N-deen)], [Ni(Pr ixa) 2( N, N,′,deen)], [Ni(Pr ixa) 2(teen) and [Ni(Pr ixa) 2 (dmso) 2]. All the complexes have been characterized by means of elemental analysis, UV-vis and IR spectroscopy, magnetochemical and conductivity measurements, and thermal analyses as octahedral complexes of bivalent nickel. The X-ray structure of [Ni(Pr ixa) 2 (pyr)] n shows a linear chain structure in which the 1,4-pyrazine ligands form bridges among nickel(II) ions, which have trans-octahedral geometry. The distances among the nickel atoms in the linear chains are 7.085(1) Å. The nearly constant value of the effective magnetic moment (3.03–3.08 μ eff/μ B) over the temperature range of 72–298 K indicated the absence of exchange interactions in polymeric [Ni(Pr ixa 2(pyr)] n . Copyright C̊ 1996 Elsevier Science Ltd