Synthesis of non-precious metal complexes (Al, Mg, Zn) and their catalytic application in isocyanate reduction

Abstract

This study reports the synthesis and characterization of a series of non-precious metal complexes (C1–C7) and their application in the reduction of isocyanates. Notably, organoaluminium complex C5 effectively catalysed the hydroalkoxylation of isocyanates to urethane products with excellent yields under mild, base-free conditions, demonstrating significant potential in green chemistry. Additionally, organozinc complex C1 was highly efficient in catalyzing the hydroboration of isocyanates, affording formamides and N-methylamines. Mechanistic insights into both transformations were explored through stoichiometric experiments as well as theoretical studies, and plausible catalytic pathways were proposed. This work provides an eco-friendly alternative to traditional precious metal catalysts, advancing sustainable synthetic methodologies in isocyanate reduction.