Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Rd., Shanghai, 200062, China.
Chem Commun (Camb). 2020 Apr 4;56(26):3721-3724. doi: 10.1039/d0cc00265h. Epub 2020 Feb 28.
Herein, we report a highly diastereo- and enantioselective allylic alkylation of oxazolones with 1,3-dienes by palladium-hydride catalyst under base-free conditions. With DTBM-SEGPHOS as the chiral ligand, a series of enantioenriched oxazolones bearing tertiary carbon centers were synthesized from substituted 1,3-dienes via exclusive 1,2-addition with moderate to good diastereoselectivities and high enantioselectivities. When simple 1,3-butadiene was used as the allyl precursor under this base-free catalytic system, 1,4-addition products were obtained in good yields with high regioselectivities.
在此,我们报告了在无碱条件下,钯-氢催化剂促进恶唑酮与 1,3-二烯的高非对映选择性和对映选择性烯丙基烷基化反应。以 DTBM-SEGPHOS 为手性配体,通过取代的 1,3-二烯的专属 1,2-加成,合成了一系列含有叔碳中心的手性恶唑酮,具有中等至良好的非对映选择性和高对映选择性。当简单的 1,3-丁二烯作为烯丙基前体在这个无碱催化体系中使用时,以高区域选择性获得了良好收率的 1,4-加成产物。