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

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.