An aluminum(iii) picket fence phthalocyanine-based heterogeneous catalyst for ring-expansion carbonylation of epoxides

Abstract

An effective heterogeneous catalyst for ring-expansion carbonylation of epoxides may have additional advantages over the homogeneous counterpart in terms of facile product separation and recyclability. A new Al(III) picket fence phthalocyanine complex was synthesized and directly knitted using the Friedel–Crafts reaction to prepare a solid porous network, which was ultimately used to immobilize [Co(CO)₄]⁻ ions. The resulting heterogeneous catalyst, [Lewis acid]⁺[Co(CO)₄]⁻, efficiently catalyzes the conversion of various epoxides into the corresponding β-lactones with high selectivity (99%) and stoichiometric conversion under mild reaction conditions, along with good functional group tolerance.