Effect of an Al(III) Complex on the Regio- and Stereoisomeric Formation of Bicyclic Organic Carbonates

Valorization of carbon dioxide into organic molecules using catalytic approaches has witnessed an upsurge in recent years. Here, the influence of an Al(III) aminotriphenolate complex on the regio- and stereochemical features of the coupling between carbon dioxide and a cyclic epoxy alcohol has been studied. Three distinct bicyclic carbonate products were produced from a single starting material, depending on the catalytic conditions. The proposed carbonate configurations were examined by solution and solid-phase techniques, including NMR spectroscopic and X-ray crystallographic analyses. Control experiments combined with DFT calculations provide a rationale for the distinct catalytic manifolds observed in the presence and absence of the Al(III) complex.