Three powerful dinuclear metal–organic catalysts for converting CO2 into organic carbonates

Abstract

Developing efficient catalysts for converting carbon dioxide (CO₂) into varied organic carbonates is an important scientific goal. By using the NH₂-functionalized tripodal ligand 2-((bis(2-aminoethyl)amino)methyl)phenol (HL), three dinuclear metal–organic complexes [Zn(L)]₂·2ClO₄ (1), [Cu(L)]₂·2ClO₄·2H₂O (2) and [Cd(L)]₂·2ClO₄ (3) have been successfully isolated and structurally characterized using single-crystal X-ray diffraction analyses. Considering the dinuclear metal centers and the NH₂-functional groups in the structures, 1–3 were investigated as catalysts for converting CO₂ into organic carbonates, and the results show that 1–3 exhibit an outstanding ability for converting CO₂ into varied organic carbonates at atmospheric pressure (0.1 MPa). The catalytic system also displays a wide substrate scope and high catalytic activity, and the reaction mechanism has been proposed herein.