A nickel catalyst for the addition of organoboronate esters to ketones and aldehydes.
A Ni(cod)(2)/IPr catalyst promotes the intermolecular 1,2-addition of arylboronate esters to unactivated aldehydes and ketones. Diaryl, alkyl aryl, and dialkyl ketones show good reactivity under mild reaction conditions (< or = 80 degrees C, nonpolar solvents, no strong base or acid additives). A dramatic ligand effect favors either carbonyl addition (IPr) or C-OR cross-coupling (PCy(3)) with aryl ether substrates. A Ni(0)/Ni(II) catalytic cycle initiated by the oxidative cyclization of the carbonyl substrate is proposed.
Bouffard
Jean
J
Department of Chemistry, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan.
Itami
Kenichiro
K
D000438:Alcohols / Q000138:chemical synthesis / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry*; D001897:Boronic Acids / Q000737:chemistry*; D002384:Catalysis; D003500:Cyclization; D004952:Esters / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D013237:Stereoisomerism
D000438:Alcohols; D000447:Aldehydes; D001897:Boronic Acids; D004952:Esters; D007659:Ketones; D009942:Organometallic Compounds; D009532:Nickel