Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012, India.
Centre for Materials Characterization, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India.
Angew Chem Int Ed Engl. 2021 May 25;60(22):12264-12268. doi: 10.1002/anie.202016938. Epub 2021 Apr 22.
Although the construction of axially chiral C-C bonds leading to the atroposelective synthesis of biaryls and allied compounds are well-known, the related synthesis of compounds bearing axially chiral C-N bonds are relatively rare. Described herein is the N-heterocyclic carbene-catalyzed atroposelective synthesis of N-aryl succinimides having an axially chiral C-N bond via the desymmetrization of N-aryl maleimides. The NHC involved intermolecular Stetter-aldol cascade of dialdehydes with prochiral N-aryl maleimides followed by oxidation afforded N-aryl succinimides in good yields and ee values. Preliminary studies on rotation barrier for the C-N bond, the temperature dependence, and detailed DFT studies on mechanism are also provided.
尽管构建轴手性 C-C 键以实现联芳基和相关化合物的对映选择性合成是众所周知的,但含有轴手性 C-N 键的化合物的相关合成相对较少。本文描述了通过 N-芳基马来酰亚胺的去对称化,N-杂环卡宾催化的具有轴手性 C-N 键的 N-芳基琥珀酰亚胺的对映选择性合成。所涉及的 NHC 进行了二醛与前手性 N-芳基马来酰亚胺的分子间 Stetter-aldol 级联反应,然后进行氧化,以良好的收率和 ee 值得到 N-芳基琥珀酰亚胺。还提供了关于 C-N 键旋转势垒、温度依赖性和详细 DFT 研究的初步研究。