Synthesis of Cyclic Carbonates from Olefins and CO2 over Zeolite-Based Catalysts

Metal phthalocyanine complexes (MPc; M = Cu²⁺, Co²⁺, Ni²⁺ and Al³⁺) encapsulated in zeolite-Y exhibit high catalytic activity for the cycloaddition of CO₂ to epichlorohydrin and propylene oxide yielding the corresponding cyclic carbonates. The catalysts could be separated easily from the reaction mixture and reused with little loss in activity. These environmentally benign catalysts are also more efficient than either the neat complexes or those obtained by supporting them on solids like silica.