Organocatalysis has in many cases supplanted the use of chiral Lewis acids in asymmetric synthesis.  Central in organocatalysis has been the develoment of secondary amine catalysts, which can be used for both iminium and enamine catalysis, and has been widely applied in, cycloadditions, nucleophilic additions to enals and alpha-functionalization of carbonyl substrates.  A particularly challenging class of substrates for organocatlytic reactions are those that contain alpha-branching, and development of suitable catalysts is still an area ripe for discovery.  We have identified cyclic hydrazide catalysts, particularly diazepane carboxylates, as being uniquely reactive in the iminium catalysis of alpha-branched enals. This was initially discovered during the develoment of an organocatalytic Cope rearrangement and has subsequently been applied to Diels-Alder cycloadditions and in Michael additions of electron rich aromatics. Understanding the mechanism of the organocatalytic Cope rearrangement has opened up opportunities to expand the repertoire of these catalysts.  This talk will discuss the development of cyclic hydrazide catalysts and their application to polyene cyclizations and a tandem oxy-Cope/Michael addition.

Prof. Dr. James L. Gleason / McGill University, Montreal