A Nickel Catalyst for the Addition of Organoboronate Esters to Ketones and Aldehydes
作者:Jean Bouffard、Kenichiro Itami
DOI:10.1021/ol9017613
日期:2009.10.1
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 (≤80 °C, nonpolar solvents, no strong base or acid additives). A dramatic ligand effect favors either carbonyl addition (IPr) or C−OR cross-coupling (PCy3) with aryl ether substrates. A Ni(0)/Ni(II)
Ni(cod)2 / IPr催化剂可促进芳基硼酸酯的分子间1,2-加成至未活化的醛和酮。二芳基,烷基芳基和二烷基酮在温和的反应条件下(≤80°C,非极性溶剂,无强碱或强酸添加剂)显示出良好的反应活性。显着的配体效应有利于羰基加成(IPr)或与芳基醚底物的C-OR交叉偶联(PCy 3)。提出了由羰基底物的氧化环化引发的Ni(0)/ Ni(II)催化循环。