This starter grant award to Columbia University supports the research of Professor James L. Leighton. The research targets the development of a new class of chiral Lewis acid catalysts for the addition of a wide range of nucleophiles to any aldehyde. Hetero-bimetallic chiral Lewis acids are designed and synthesized that simultaneously employ two binding elements, a simultaneous sigma and pi binding, to control the addition of nucleophiles to aldehydes. Following synthesis of the catalysts, their complexation reactions are studied in detail and the complexes fully characterized spectroscopically. The catalytic properties are optimized by examination of various bimetal combinations. The research impacts the field of asymmetric catalysis in a practical way, in that new catalysts are made available for the asymmetric synthesis of small organic molecules. In addition, the studies address fundamental mechanistic questions about the nature of pi-bound aldehyde-metal complexes.
