Cyclic(alkyl)(amino)carbene (CAAC) ligands are found to perturb regioselectivity of the copper-catalyzed carboboration of terminal alkynes, favoring the less commonly observed internal alkenylboron regiosomer through an α-selective borylcupration step. A variety of carbon electrophiles participate in the reaction, including allyl alcohol derivatives and alkyl halides. The method provides a straightforward
环(烷基)(
氨基)卡宾 (
CAAC)
配体被发现会扰乱末端
炔烃的
铜催化碳
硼化的区域选择性,通过 α-选择性
硼基
铜化步骤有利于不太常见的内部烯基
硼区域异构体。多种碳亲电子试剂参与反应,包括
烯丙醇衍
生物和卤代烷。该方法为通用的三取代烯基
硼化合物提供了一种直接且选择性的途径,否则很难获得这些化合物。