The reaction between an alkyllithium homocuprate and an α-bromoketone yields the corresponding alkylated ketone. This alkylation method allows the regiospecific introduction of a primary, secondary, or a tertiary alkyl group on the ketone at the site initially brominated. Two concomitant mechanisms, halogen-metal exchange and nucleophilic substitution, explain this new reaction. While these two mechanisms
均
锂烷基
锂与α-
溴代酮之间的反应产生相应的烷基化酮。该烷基化方法允许在最初
溴化的位点在酮上区域特异性地引入伯,仲或叔烷基。两种伴随的机理,卤素
金属交换和亲核取代,解释了这一新反应。虽然这两种机制在伯烷基和仲烷基取代中共存,但在叔烷基的情况下似乎只有亲核取代是可能的。