Department of Chemistry, Yale University , 225 Prospect Street, New Haven, Connecticut 06520, United States.
Medicinal Sciences, Pfizer, Inc. , Groton, Connecticut 06340, United States.
J Org Chem. 2017 Sep 1;82(17):9243-9252. doi: 10.1021/acs.joc.7b01723. Epub 2017 Aug 22.
Herein, we report a Rh(I)/bisphosphine/KPO catalytic system allowing for the first time the selective branched C-H alkylation of benzimidazoles with Michael acceptors. Branched alkylation with N,N-dimethyl acrylamide was successfully applied to the alkylation of a broad range of benzimidazoles incorporating a variety of N-substituents and with both electron-rich and -poor functionality displayed at different sites of the arene. Moreover, the introduction of a quaternary carbon was achieved by alkylation with ethyl methacrylate. The method was also shown to be applicable to the C2-selective branched alkylation of azabenzimidazoles.
在此，我们报告了一个 Rh(I)/双膦/KPO 催化体系，该体系首次允许迈克尔受体对苯并咪唑进行选择性支链 C-H 烷基化。N,N-二甲基丙烯酰胺的支链烷基化成功地应用于包括各种 N-取代基的广泛的苯并咪唑的烷基化，并且在芳环的不同位置显示出富电子和缺电子官能团。此外，通过与甲基丙烯酸乙酯的烷基化实现了季碳原子的引入。该方法也被证明适用于氮杂苯并咪唑的 C2-选择性支链烷基化。
