Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of Chemistry, Northeast Normal University, Changchun 130024, China.
Warshel Institute for Computational Biology, School of Life and Health Sciences, The Chinese University of Hong Kong (Shenzhen), Shenzhen 518172, China.
Org Lett. 2020 May 1;22(9):3524-3530. doi: 10.1021/acs.orglett.0c00963. Epub 2020 Apr 15.
A new type of coupling between unactivated olefins and nonstabilized alkyl radicals was achieved, which enabled the first intermolecular Heck-type reaction of cycloketone oxime esters and unactivated alkenes. This directing-group-based strategy was compatible with various unactivated alkenes and cyclobutanone-, cyclopentanone-, and cyclohexanone-derived oxime esters. Density functional theory calculations showed that both excellent regioselectivities and good diastereoselectivities could be ascribed to the 2-butanol-assisted concerted H-OBz elimination of the conformationally strained metallacyclic transition state.
实现了未活化烯烃和非稳定烷基自由基之间的新型偶联，从而首次实现了环酮肟酯和未活化烯烃的分子间 Heck 型反应。这种基于导向基团的策略与各种未活化烯烃以及环丁酮、环戊酮和环己酮衍生的肟酯兼容。密度泛函理论计算表明，优异的区域选择性和良好的非对映选择性都可以归因于构象应变的金属环过渡态的 2-丁醇辅助协同 H-OBz 消除。
