Selective monochlorination of unsymmetrical vicinal diols with chlorinated iminium chlorides
作者:Liqun Yang、Xiaotong Li、Yu Wang、Chengyang Li、Xiaoyu Wu、Zhaoguo Zhang、Xiaomin Xie
DOI:10.1016/j.tet.2020.131114
日期:2020.4
Chlorinated iminium chlorides have been identified to promote the highly efficient and selective mono-chlorination of unsymmetrical vicinal diols. Vilsmeier reagent, namely, (chloromethylene)dimethyliminium chloride, enables highly reactive and regioselective chlorination of 1,2- and 1,3-diols featured one secondary benzylic hydroxy group and one primary aliphatic hydroxy group to give the corresponding
已发现氯化亚胺氯化物可促进不对称邻位二醇的高效和选择性单氯化。Vilsmeier试剂,即(氯亚甲基)二甲基亚胺氯化物,能够对具有一个仲苄基羟基和一个伯脂族羟基的1,2-和1,3-二醇进行高反应性和区域选择性氯化,从而生成相应的1,2-和1 ,3-氯代醇。Viehe盐(α,α-二氯亚胺盐)显示出出色的反应性和邻邻二醇的良好选择性,可以通过环状中间体就地生成相应的氯醇氨基甲酸酯。氯化方案可耐受各种官能团,包括卤素,萘环,硝基和氰基。此外,在该氯化反应过程中可以保持手性二醇的光学纯度。