Synthesis of novel aminoboronic acid derivatives using metal-catalyzed hydroborations

ORGN 143

Stephen A. Westcott, Stephen J. Scales, Hanni A. Darwish, Daniel I. McIsaac, Jonathan D. Webb, and Christopher M. Vogels. Department of Chemistry, Mount Allison University, 63C York Street, Sackville, NB E4L 1G8, Canada
The bioorganic chemistry of boron-containing compounds is an area of growing interest. Boronic acids and boronate esters have been found to facilitate the transport of various ribonucleosides in and out of liposomes, an important attribute in the area of drug design. Simple aminoboron compounds have also found some utility in BNCT. As a result, much effort has focused on the synthesis of boron-containing amino acid and peptide derivatives. The incorporation of a Lewis base and a Lewis acidic boronic acid functionality into the same molecule, however, is a notoriously difficult procedure and synthetic routes to these compounds are scarce. New effective methods to prepare heteroatom containing boron compounds will have a tremendous impact on bioinorganic and pharmaceutical chemistry. We report herein that the metal catalyzed hydroborations of various substrates with catecholborane or pinacolborane can be used to give the corresponding derivatives containing boronate ester appendages.