title: Copper-catalyzed nondecarboxylative cross coupling of alkenyltrifluoroborate salts with carboxylic acids or carboxylates: synthesis of enol esters.
abstract: A mild copper-catalyzed Chan-Lam-Evans type cross-coupling reaction for the regioselective and stereospecific preparation of (E)- or (Z)-enol esters is described. The method couples carboxylate salts or carboxylic acids with potassium alkenyltrifluoroborate salts in the presence of catalytic CuBr and DMAP with 4 Å molecular sieves under O2 at 60 °C. Overall, this method demonstrates carboxylic acids as suitable reaction partners for nondecarboxylative copper-catalyzed cross-couplings to form C-O bonds in an Ullmann-like reaction.
authors.affiliation: Davenport Research Laboratories, Department of Chemistry, University of Toronto , 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
authors.forename: Fang
authors.initials: F
authors.lastname: Huang
authors.forename: Tan D
authors.initials: TD
authors.lastname: Quach
authors.forename: Robert A
authors.initials: RA
authors.lastname: Batey