Spectroscopic and electrochemical study of copper and zinc complexes with a N2S2 ligand donor set. Crystal structure of the copper(II) complex derived from 1,3-propylenediamine and 3-formyl-1-phenyl-2(1H)-pyridinethione

Abstract

The copper(I) and zinc(II) analogues of a series of Cu^II–N₂S₂ complexes of bis(imine) ligands derived from the condensation of 3-formyl-1 -phenyl-2(1H)-pyridinethione and diamines are described, together with the electrochemical properties of the couple Cu^II–Cu^I and the crystal structure of the copper(II) complex of the ligand obtained from 1,3-propylenediamine. The complex crystallizes in the centrosymmetric space group P with a= 16.111(4), b= 11.194(4), c= 8.681(2)Å, α= 106.81(2), β= 96.47(2), γ= 95.38(2)°, Z= 2, and R= 0.073 for 3 328 reflections with I > 3σ(I). The copper atom is equatorially co-ordinated to two imine nitrogens [Cu–N 1.980(5) and 1.989(5)Å] and two sulphur atoms [Cu–S 2.259(2) and 2.288(2)Å], and weakly bound to an oxygen atom of a perchlorate anion in an axial position [Cu–O 2.635(5)Å]. The CuN₂S₂ centre displays a slightly tetrahedrally distorted planar arrangement.