Bimetallic poly- and oligo-nuclear complexes based on a rhodium(III) metalloligand

Interaction of trans-[Rh(i-Nic)4Cl2]3− anions (i-Nic− – isonicotinate anion) with Cuaq2+ and Coaq2+ cations in water has afforded complex salts Co3[Rh(i-Nic)4Cl2]2·17H2O (1) and Cu3[Rh(i-Nic)4Cl2]2·14H2O (2). Oligonuclear character of 1 and 2 has been established. A coordination polymer Cu5[Rh(i-Nic)4Cl2]2(i-Nic)2(OH)2·2H2O (3) has been crystallized by hydrothermal treatment of 2 at 160 °C, and its structure was determined by X-ray structural analysis. EPR data for the complexes has been collected and interpreted. Thermal decomposition of the salts was studied by c-DTA. Bimetallic alloys rhodium–copper and rhodium–cobalt have been obtained as final products of thermal decomposition.

► Three new bimetallic Rh(III)M(II) (M = Co, Cu) complexes were synthesized.
► Compounds were found to have a polymeric structure.
► Thermolysis of complexes yields bimetallic alloys RhM.