Preparation, characterisation and structures of copper(II) complexes of an asymmetric anti-cancer drug analogue†

Abstract

A series of copper(II) complexes of the anti-cancer drug analogue 1,5-bis(2-pyridylmethylene)thiocarbonohydrazide (H₂L) was synthesized from acid solution. The single crystal structures of two asymmetric, binuclear, complexes [{Cu₂(HL)(H₂PO₄)₂}₂][NO₃]₂·2H₂O and [{Cu₂(HL)(CF₃CO₂)₃}₂] and two mononuclear, monomeric complexes [Cu(H₃L)(H₂O)][ClO₄]₃·2H₂O and [Cu(H₃L)(NO₃)₂]NO₃ were solved. The binuclear complexes are dimeric with three-atom anion bridges. Selective removal of one copper ion gives mononuclear monomers. The primary magnetic exchange is between copper(II) centres within a planar binuclear unit with weaker interactions via anion or sulfur bridges.