Synergetic effect in heterogeneous acid catalysis by a porous ionic crystal based on Al(iii)–salphen and polyoxometalate

Abstract

A porous ionic crystal is synthesized with a cationic Al(III)–salphen complex (Al(III)–salphen) and a α-Keggin-type polyoxometalate (POM). The compound possesses stable three dimensional porous structure and shows high activity as a heterogeneous catalyst in pinacol rearrangement, which is a typical acid reaction. Notably, Al(III)–salphen, POM, and a physical mixture of the two components are much less active, suggesting a synergetic effect of Al(III)–salphen and POM in a porous framework.