Enantio- and Diastereoselective Synthesis of Spiro-epoxyoxindoles

An asymmetric synthesis of epoxyoxindoles from isatins has been developed by employing chiral sulfur ylides generated in situ from camphor-derived sulfonium salts. This reaction allows an efficient access to enantioenriched spiro-epoxyoxindoles under mild reaction conditions, featuring high yields and excellent enantio- and diastereoselectivities.本研究开发了一种以樟脑衍生锍盐（camphor-derived sulfonium salts）原位生成的手性硫叶立德（chiral sulfur ylides）作为试剂，由靛红（isatins）合成环氧羟吲哚（epoxyoxindoles）的不对称合成方法。该反应可在温和反应条件下高效制备对映体富集的螺环氧羟吲哚（spiro-epoxyoxindoles），且具有高收率与优异的对映选择性及非对映选择性。