Lewis Base Assisted Brønsted Base Catalysis: Direct Regioselective Asymmetric Vinylogous Alkylation of Allylic Sulfones
作者:Lin Jiang、Qian Lei、Xin Huang、Hai-Lei Cui、Xue Zhou、Ying-Chun Chen
DOI:10.1002/chem.201100534
日期:2011.8.16
A Lewis base assisted Brønsted base catalysis (LBABB) strategy is applied for direct asymmetric vinylogous alkylation of allylic sulfones with Morita–Baylis–Hillman (MBH) carbonates, in which a strong Brønsted base, tert‐butoxy anion, generated in situ from a tertiary amine catalyst and MBH carbonate, is crucial in activating unstabilized nucleophiles. The γ‐regioselective alkylation products were
刘易斯碱辅助的布朗斯台德碱催化(LBABB)策略适用于烯丙基砜与森田-贝利斯-希尔曼(MBH)碳酸盐的直接不对称乙烯基烷基化反应,其中强叔酸,叔丁氧基阴离子是由叔酸原位生成胺催化剂和MBH碳酸酯对于活化不稳定的亲核试剂至关重要。当用改性的金鸡纳生物碱催化时,获得的γ-区域选择性烷基化产物具有良好的对映体过量值。