Novel bifunctional chiral squaramide-amine catalysts for highly enantioselective addition of mono and diketones to nitroalkenes
作者:Ze Dong、Xiaoqing Jin、Pengcheng Wang、Chang Min、Jin Zhang、Zhe Chen、Hai-Bing Zhou、Chune Dong
DOI:10.3998/ark.5550190.0012.927
日期:——
Novel bifunctional chiral squaramide–amine organocatalysts have been developed by rational combination of pyrrolidine and a cinchona alkaloid. The catalysts promoted the enantioselective Michael addition of both mono- and diketones to a broad range of nitroalkenes providing the corresponding products in moderate to high yields with excellent enantioselectivities and diastereoselectivities (up to 96%
通过吡咯烷和金鸡纳生物碱的合理组合开发了新型双功能手性方酸酰胺-胺有机催化剂。该催化剂促进了单酮和二酮对广泛范围的硝基烯烃的对映选择性迈克尔加成,以中等至高产率提供相应的产物,具有优异的对映选择性和非对映选择性(产率高达 96%,96% ee,98:2 dr)。条件温和。这些结果表明,将两个手性特权骨架、吡咯烷和辛可宁与方酸酰胺连接器组装在一起是实现更广泛底物范围、高反应效率和对映选择性的有用策略。嵌入催化剂的两个主链之间手性的匹配对于提高对映选择性也很关键。