Linking thione-ligated copper(I) centres with trans-1,2-bis(diphenylphosphino)ethene (trans-dppen): crystal structures of the pyrimidine-2-thione derivatives [CuBr(mu(2)-trans-dppen)(pymtH)](2) and [CuI(mu(2)-trans-dppen))(pymtH)](2)

摘要

Several mixed-ligand complexes of the composition [CuX(trans-dppen)(L)] (X = Br, I) have been prepared by treatment of copper(I) halide with equimolar amounts of trans-1,2-bis(diphenylphosphino)ethene (trans-dppen) in acetonitrile followed by the addition of a methanolic solution of one equivalent of a heterocyclic thione (L). The novel complex compounds have been characterized by H-1 NMR and IR spectroscopy as well as by elemental analyses and melting points. The X-ray structures of two representative examples, namely the pyrimidine-2-thione complexes of copper(I) bromide and iodide confirm that the compounds are dimers of type [CuX(mu(2)-trans-dppen)(L)](2) containing two tetrahedral coordination units joined by two diphosphine bridges. (C) 2004 Elsevier Ltd. All rights reserved.