Bimetallic Salen-Based Compounds and Their Potential Applications

The new bimetallic coordination compounds [LNiAg­(NO₃)], [LCuMn­(NO₃)₂], [LCuCu­(NO₃)₂], [LCuZn­(NO₃)₂], and [{LCuBi­(NO₃)₃}­(ACN)] have been synthesized from a salen-type ligand L containing two distinct coordination sites to accommodate (different) metal ions M1 and M2. In the solid state, the formation of 1:1 compounds (LCu:M2) is always observed, but interactions between the compounds lead to differences in packing. For example, a head-to-tail arrangement along the crystallographic <i>b</i>-axis is observed in the case of the LCuBi compound, and the LNiAg compound is polymeric, while its Cu homologue LCuAg forms a discrete dimer. Given the inherent potential of the preorganizing, two metal ions using L could be used to synthesize nanoscale copper–bismuth and −manganese mixed metal oxides as a function of the temperature. The combination of different bioactive metal ions within one ligand system was furthermore explored for antimicrobial efficiency.