Calcium(II)-Catalyzed Intra- and Intermolecular Hydroamidation of Unactivated Alkenes in Hexafluoroisopropanol
作者:Chenxiao Qi、Felix Hasenmaile、Vincent Gandon、David Lebœuf
DOI:10.1021/acscatal.7b04271
日期:2018.3.2
found to be a highly efficient promoter system for the intra- and intermolecular hydroamidation of unactivated alkenes. Unlike other methods, a vast array of functional groups is tolerated at the nitrogen and alkene moieties. The reaction produces the corresponding nitrogen-containing compounds in excellent yields and good diastereoselectivities. The use of HFIP as solvent proved crucial for the proper
发现三氟化钙(II)盐和六氟异丙醇(HFIP)的组合是用于未活化烯烃的分子内和分子间加氢酰胺化的高效促进剂体系。与其他方法不同,在氮和烯烃部分可以容忍大量官能团。该反应以优异的产率和良好的非对映选择性产生了相应的含氮化合物。事实证明,使用HFIP作为溶剂对于正确进行此转化至关重要。通过DFT计算合理化了它的作用,以及钙及其NTf 2配体的作用。这些计算表明[(NTf 2)Ca(HFIP)n ] +配合物如何通过NTf的碱性位点活化酰胺。2个配体和烯烃带有一个酸性HFIP质子。与钙中心的配位会加剧HFIP的酸度,随着n的增加而增加。