Synthesis of Hetero-multinuclear Metal Complexes by Site-Selective Redox Switching and Transmetalation on a Homo-multinuclear Complex

Abstract

Hetero-multinuclear metal complexes are a promising class of compounds applicable to photoluminescence, magnetism, and catalysis. In this work, we have developed a synthetic method for hetero-tetranuclear metal complexes by combining advantages of site-selective redox switching and transmetalation. First, a homo-tetranuclear Co^II₄ complex was converted to a mixed-valence Co^IIICo^II₃ complex by site-selective oxidation, which was then transmetalated from Co^II to Ni^II to form a heterometallic Co^IIINi^II₃ complex. Finally, a Co^IINi^II₃ complex was synthesized by metal-selective reduction on the Co^III site. The basic structural frameworks of the main products in the whole process starting from the Co^II₄ complex are isostructural. Notably, the Co^IINi^II₃ complex was not accessible by direct mixing of ligand, Co^II, and Ni^II. This method would provide an alternative strategy for highly selective synthesis of hetero-multinuclear metal complexes.