Macromolecular materials in heterogeneous catalysis: an aluminium silasesquioxane gel as active catalyst in Diels–Alder reactions of enones

Abstract

A highly active, genuinely heterogeneous catalyst for liquid-phase Diels–Alder reactions of enones results from the silanol centred modification of an incompletely condensed silasesquioxane with trimethylaluminium, the resulting catalytic material being a gel that contains aluminium(III) siloxy functions (Al–O–Si) which are incorporated in a well defined, three-dimensional SiO framework.