Chiral Spiro Phosphoramide-Catalyzed Sulfa-Michael Addition/Enantioselective Protonation of Exocyclic Enones
作者:Yi-Pan Li、Shou-Fei Zhu、Qi-Lin Zhou
DOI:10.1021/acs.orglett.9b03615
日期:2019.12.6
A highly efficient asymmetric Michael addition of thiols to exocyclic enones was achieved by using chiral spiro phosphoramide catalysts. The precisely chiral control in the protonation of the enol intermediate ensured high enantioselectivity. The reaction features high activity (yields up to 99%, turnover numbers up to 8400) and high enantioselectivity (up to 97% ee) with a broad substrate scope, and
A highly enantioselective nickel-catalyzed intramolecular hydroalkenylation of N- or O-tethered 1,6-dienes was developed by using monodentate chiral spiro phosphoramidite ligands. The reaction provides an efficient and straightforward method for preparing very useful six-membered N- and O-heterocycles with high regioselectivity as well as excellent stereoselectivity from easily accessible starting
通过使用单齿手性螺亚磷酰胺配体开发了高度对映选择性镍催化的 N 或 O 系链 1,6-二烯的分子内加氢烯基化。该反应提供了一种有效且直接的方法,可以在温和的反应条件下从易于获得的起始材料中制备非常有用的六元 N-和 O-杂环,具有高区域选择性和优异的立体选择性。本研究中开发的手性螺镍催化剂是为数不多的用于非共轭二烯高度对映选择性环化的催化剂之一。