Synthesis and crystal structure of hexanuclear copper(I) complexes of µ3-pyridine-2-thionate

Abstract

1H-Pyridine-2-thione (C₂H₄NSH) reacts with [Cu(MeCN)₄]PF₆ in acetone to give an orange compound [Cu₆(C₅H₄NS)₆], which crystallized in the monoclinic space group P2₁/n, a= 12.257(2), b= 16.029(2), c= 9.581 (1)Å, β= 108.859(9)°, and Z= 2. The single-crystal X-ray structure of the complex shows a distorted octahedral core of six copper atoms, with metal–metal distances ranging from 2.795(1) to 3.160(1)Å. Each copper has a trigonal geometry constituted by the two thiolate sulphur and one pyridine nitrogen atoms, as distinct from the common copper–thione sulphur co-ordination in other copper(I)–C₅H₄NSH complexes. The copper atom deviates highly from the S₂N co-ordination plane. The reaction solution was examined by ¹H n.m.r. spectroscopy, which reveals the formation of several low-molecular-weight species in the early stages of the reaction.