Selective Reductions of Cyclic 1,3-Diesters by Using SmI<sub>2</sub>and H<sub>2</sub>O
作者:Karl D. Collins、Juliana M. Oliveira、Giuditta Guazzelli、Brice Sautier、Sara De Grazia、Hiroshi Matsubara、Madeleine Helliwell、David J. Procter
DOI:10.1002/chem.201000632
日期:2010.9.3
SmI2/H2O reduces cyclic 1,3‐diesters to 3‐hydroxyacids with no over reduction. Furthermore, the reagent system is selective for cyclic 1,3‐diesters over acyclic 1,3‐diesters, and esters. Radicals formed by one‐electron reduction of the ester carbonyl group have been exploited in intramolecular additions to alkenes. The ketal unit and the reaction temperature have a marked impact on the diastereoselectivity
SmI 2 / H 2 O可以将环状1,3-二酯还原为3-羟基酸,且不会过度还原。此外,该试剂系统对环状1,3-二酯的选择要高于非环状1,3-二酯和酯的选择。通过单电子还原酯羰基形成的自由基已在分子内加成烯烃中得到利用。缩酮单元和反应温度对环化的非对映选择性具有显着影响。当起始环二酯中存在两个烯烃并导致形成两个具有良好立体控制性的环和四个立体中心时,可能会发生级联级联反应。