Enantioselective Construction of Aryl-Substituted All-Carbon Quaternary Stereocenters by Using Tertiary Amine-Thiourea-Catalyzed Michael Additions
作者:Peng Chen、Xu Bao、Le-Fen Zhang、Guo-Jie Liu、Yi-Jun Jiang
DOI:10.1002/ejoc.201501420
日期:2016.2
A catalytic enantioselective synthetic strategy for the aryl-substituted all-carbon quaternary stereocenters of bioactive hydrodibenzofuran alkaloids was achieved by the Michael addition reaction of α-cyano ketones and acrylates using a chiral tertiary amine–thiourea catalyst. This method can tolerate steric bulkiness and multiple functional groups, and 32 Michael adducts were prepared in good to excellent
生物活性氢化二苯并呋喃生物碱的芳基取代的全碳季立体中心的催化对映选择性合成策略是通过使用手性叔胺-硫脲催化剂的 α-氰基酮和丙烯酸酯的迈克尔加成反应实现的。这种方法可以容忍空间体积和多个官能团,并且以良好到极好的收率制备了 32 种迈克尔加合物,并具有中等到良好的对映选择性。一次重结晶后,产物的对映体纯度也可以提高到 99% ee。这种对映选择性迈克尔加成具有低成本、无金属且易于操作的程序,可以提供四克规模的多功能对映纯迈克尔加合物,并为许多氢化二苯并呋喃天然产物提供足够数量的潜在前体。