γ,δ-Unsaturated amides in which the alkene moiety bears an aryl or heteroaryl substituent undergo regioselective rhodium-catalyzed δ-borylation by pinacolborane to afford chiral secondary benzylic boronic esters. The results contrast the γ-borylation of γ,δ-unsaturated amides in which the disubstituted alkene moiety bears only alkyl substituents; the reversal in regiochemistry is coupled with a reversal
γ,δ-不饱和酰胺(其中烯基部分带有芳基或杂芳基取代基)通过
频哪醇硼烷进行区域选择性
铑催化的δ-
硼化,从而获得手性仲苄基
硼酸酯。结果对比了γ,δ-不饱和酰胺的γ-
硼化,其中双取代的烯烃部分仅带有烷基取代基。区域
化学的逆转与π-面部选择性意义上的逆转相结合。