Synthesis of Enantioenriched Heterocycles by Tandem Sakurai Allylation/Intramolecular Cyclization Processes

Abstract

Organosilanes are advantageous in organic synthesis due to their ability to act as both stable products and reactive intermediates. A stereospecific one-pot cascade reaction that converts chiral allylic silanes into chiral heterocycles was developed using Lewis acid catalysis. We report on the development of this cascade reaction, optimization to benchtop- scale chemistry, and preliminary investigation into the synthetic scope. In our studies, we were successful in varying the cyclization ring size, investigating cyclization preference in the presence of multiple electrophilic leaving groups, and altering the functional groups present on the aldehyde starting material. Ultimately, we envision this method will be useful in the synthesis of a variety of enantioenriched heterocycles found in bioactive natural products, many of which have may find use as potential drug targets.