Catalytic Dehydrative Peptide Synthesis with gem-Diboronic Acid

摘要

A general approach for amide synthesis is based on stoichiometric activation of carboxylic acid using coupling reagents. Though this method is highly reliable, reagent-derived side products are inevitably generated. In sharp contrast, organoboron reagents have been realized as an ideal catalyst for dehydrative amidation, producing only water as waste. In particular, a detail investigation of substituent effects of arylboronic acids provided several highly active catalysts for amide condensation. However, catalytic condensation of α-amino acids is still difficult even with the reported arylboronic acids, and the development of finely engineered organoboron catalysts is thus necessary for catalytic dehydrative peptide synthesis. To overcome this issue, we designed gem-diboronic acid as a new class of organoboron catalyst, which is based on the recent mechanistic insights of boronic acid-catalyzed amidation.