Metal-Catalyzed Reactions of Organoboronic Acids and Esters

Metal-catalyzed B-C and C-C bond-forming reactions of organoboronic acids that have been pursued in the past three decades by our group are summarized in this article. B-C bond-forming reactions for the synthesis of organoboronic acid derivatives include metal-catalyzed addition reactions of pinacolborane or catecholborane (hydroboration), bis(pinacolato)diboron (diboration), and alkylthioboranes (thioboration) to alkenes, alkynes, 1,3-alkadienes, or 1,2-alkadienes (allenes). Other B-C bond-forming reactions include coupling reactions of pinacolborane or bis(pinacolato)dihoron for borylation of C-halogen bonds with palladium catalysts and C-H bonds of arenes and alkenes with iridium catalysts. These reactions have provided a convenient new access to aryl-, 1-alkenyl-, allyl-, or benzylboronates. Metal-catalyzed C-C and C-N bond-forming reactions using boronic acid derivatives include synthesis of novel cyclic triolborate salts for palladium- or copper-catalyzed cross-coupling reactions with organic halides or amines, rhodium- or palladium-catalyzed 1,4-addition reactions of arylboronic acids to alpha,beta-unsaturated carbonyl Compounds and rhodium-catalyzed addition of aryl- and 1-alkenylboronic acids to aldehydes and imines.