C1-Symmetric Binap Derivative Featuring Single Diferrocenylphosphino-Donor Moiety
C1-Symmetric Binap Derivative Featuring Single Diferrocenylphosphino-Donor Moiety
复制标题
具有单个二茂铁基膦基供体部分的 C1-对称 Binap 衍生物
DOI：
10.1021/acs.organomet.1c00132
复制
发表时间：
2021
期刊：
影响因子：
2.8
通讯作者：
Ogasawara Masamichi
中科院分区：
文献类型：
--
作者：
Enomoto Yuuki;Ichiryu Hiroki;Hu Hao;Ura Yasuyuki;Ogasawara Masamichi
AC1对称的手性双膦配体FcPh-BINAP(1)是以对映体形式合成的，它具有单一的二茂铁基膦部分和一个常规的Ph2P-取代基。配体1在空间上比FC-Segphos(A)要求低，FC-Segphos(A)有两个二茂铁膦基团，在催化苯基硼酸与2-环己酮的不对称共轭加成反应中表现出比A更高的活性。配体1被应用于钯催化的两个不对称反应，即轴向手性烯的合成和分子间的Heck反应，表现出比母体BINAP更高的对映体选择性。在前一反应中，Pd/(R)-1物种比Pd/(R)-BINAP催化剂的ee提高了47%，在后者中，ee提高了39%。
AC1-symmetric chiral bisphosphine, FcPh-Binap (1), which possesses a single diferrocenylphosphino moiety together with a conventional Ph2P-substituent, was prepared in enantiomerically pure forms. Ligand1is sterically less demanding than Fc-Segphos (A), which has two diferrocenylphosphino groups, and showed higher activity thanAin the rhodium-catalyzed asymmetric conjugate addition of phenylboronic acid to 2-cyclohexenone. Ligand1was applied in the two palladium-catalyzed asymmetric reactions, namely the synthesis of axially chiral allenes and the intermolecular Heck reaction, and displayed higher enantioselectivity than parent Binap. The Pd/(R)-1species showed up to 47% ee enhancement over the Pd/(R)-Binap catalyst in the former reaction and up to 39% ee enhancement in the latter.