A Nickel Catalyst for the Addition of Organoboronate Esters to Ketones and Aldehydes

• DOI: 10.1021/ol9017613
• Publication Date: 2009-08-26T18:09:16Z
• Authors: Jean Bouffard; Kenichiro Itami
• Keywords: Reactivity; Catalytic cycle

A Ni(cod)2/IPr catalyst promotes the intermolecular 1,2-addition of arylboronate esters to unactivated aldehydes and ketones. Diaryl, alkyl aryl, dialkyl ketones show good reactivity under mild reaction conditions (≤80 °C, nonpolar solvents, no strong base or acid additives). dramatic ligand effect favors either carbonyl addition (IPr) C−OR cross-coupling (PCy3) with aryl ether substrates. Ni(0)/Ni(II) catalytic cycle initiated by oxidative cyclization substrate is proposed.