Enantioselective Nickel-Catalyzed Cross-Coupling Reactions of Trialkynylindium Reagents with Racemic Secondary Benzyl Bromides
作者:Jorge Caeiro、José Pérez Sestelo、Luis A. Sarandeses
DOI:10.1002/chem.200701035
日期:2008.1.7
first enantioselective sp-sp3 cross-coupling reaction between alkynyl organometals and racemic benzyl bromides is reported. The coupling is performed at room temperature by using NiBr2diglyme and (S)-(iPr)-Pybox as the catalytic system and trialkynylindium reagents as nucleophiles. The reaction is stereoconvergent, both enantiomers of the racemic benzyl bromide are converted into one enantiomer of the
报道了炔基有机金属与外消旋苄基溴之间的第一个对映选择性sp-sp3交叉偶联反应。通过在室温下使用NiBr2二甘醇二甲醚和(S)-(iPr)-Pybox作为催化体系和三炔基吡啶试剂作为亲核试剂进行偶联。该反应是立体收敛的,外消旋苄基溴的两种对映异构体均转化为产物的一种对映异构体,且具有立体特异性。由于三有机铟试剂转移了连接到铟上的三个有机基团(仅使用40 mol%的R3In),因此该反应有效地以高收率和高原子经济性进行。