The stabilized iminium catalyzed (E)-polyene cyclization: trapping of non-activated terminating groups enabled by cation–π interactions

Abstract

A cyclic hydrazide catalyst bearing a pendant anthracene catalyzes the polyene cyclization of 1,5-hexadiene-2-carboxaldehydes. Bicyclic closure proceeds in substrates with non-activated terminating groups that fail to react with simple hydrazide catalysts. Computational analysis shows that stabilization through cation–π interactions throughout the reaction sequence leads to the enhanced reactivity of the catalyst.