Mono- and bi-dentate phosphaalkene ligands: structures of their copper(I) chloride complexes

Abstract

While the reaction of the monophosphaalkene [(2,4,6-tri-tert-butylphenyl)phosphanediylmethyl]-benzene (L²) with copper(I) chloride led to a dimeric complex [Cu₂Cl₂L²₂(NCMe)₂]1, use of the diphosphaalkene 1,3-bis[(2,4,6-tri-tert-butylphenyl)phosphanediylmethyl]benzene (L¹) gave rise to a tetrameric complex [Cu₄Cl₄L¹₂]·3EtOH 2. The crystal structures of the complexes have been determined and indicate that 1 is a centrosymmetric dimer with tetrahedrally co-ordinated copper(I) centres, whereas 2 adopts a ‘cubane-like’ structure with pairs of copper atoms bridged by different L¹ units.