K3PO4·H2O. Preliminary mechanistic studies of the reaction identified a novel species formulated as the boronate complex, [Ni(OBOH}2-tolyl})(PhPNP)], which most likely represents a catalyst deactivation pathway. The productive catalytic cycle was found to be most consistent with a Ni(I)/Ni(III) process where the boronic acid serves as both reductant and nucleophile in the presence of base.
摘要
镍(II)络合物[NiCl(Ph
PNP)](Ph
PNP = 2,5-双(
二苯基膦甲基)
吡咯的阴离子)已被用作铃木-宫浦的芳基卤化物与碳原子的交叉偶联反应的前催化剂。
硼酸。发现在存在K3PO4·
H2O的情况下,在升高的温度下,富电子和缺电子的芳族
溴化物都以适度的产率与
硼酸偶合。对该反应的初步机理研究确定了一种新型物种,称为
硼酸酯络合物[Ni(OB OH} 2-
甲苯基})(Ph
PNP)],它很可能代表了催化剂的失活途径。发现生产性催化循环与Ni(I)/ Ni(III)过程最一致,在该过程中,
硼酸在碱存在下同时充当还原剂和亲核试剂。