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

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.