Saha Satyajit, Schneider Christoph
Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig (Germany).
Chemistry. 2015 Feb 2;21(6):2348-52. doi: 10.1002/chem.201406044. Epub 2014 Dec 8.
The highly enantioselective conjugate addition of enamides and enecarbamates to in situ-generated ortho-quinone methides, upon subsequent N,O-acetalization, gives rise to acetamido-substituted tetrahydroxanthenes with generally excellent enantio- and diastereoselectivities. A chiral BINOL-based phosphoric acid catalyst controls the enantioselectivity of the carbon-carbon bond-forming event. The products are readily converted into other xanthene-based heterocycles.
烯酰胺和烯基氨基甲酸酯与原位生成的邻醌甲基化物进行高度对映选择性共轭加成，随后进行N，O - 缩醛化反应，得到具有通常优异的对映和非对映选择性的乙酰氨基取代的四氢呫吨。一种基于手性联萘酚的磷酸催化剂控制碳 - 碳键形成反应的对映选择性。产物可容易地转化为其他基于呫吨的杂环化合物。
