Suzuki–Miyaura Cross-Coupling of 2-Pyridyl Trimethylammonium Salts by N–C Activation Catalyzed by Air- and Moisture-Stable Pd–NHC Precatalysts: Application to the Discovery of Agrochemicals
作者:Yuge Hu、Yanqing Gao、Jiuhui Ye、Zhiqing Ma、Juntao Feng、Xili Liu、Peng Lei、Michal Szostak
DOI:10.1021/acs.orglett.3c00741
日期:2023.5.5
cross-coupling of 2-pyridyl ammonium salts by highly selective N–C activation catalyzed by air- and moisture-stable Pd(II)–NHC (NHC = N-heterocyclic carbene) precatalysts. The use of well-defined and highly reactive [Pd(IPr)(3-CF3-An)Cl2] (An = aniline) or [Pd(IPr)(cin)Cl] (cin = cinnamyl) Pd(II)–NHC catalysts permits an exceptionally broad scope of the cross-coupling to furnish valuable biaryl and heterobiarylpyridines
我们报告了 2-吡啶基铵盐的第一个 Suzuki-Miyaura 交叉偶联,通过空气和水分稳定的 Pd(II)-NHC(NHC = N-杂环卡宾)预催化剂催化的高选择性 N-C活化。使用定义明确且反应性高的 [Pd(IPr)(3-CF 3 -An)Cl 2](An = 苯胺)或 [Pd(IPr)(cin)Cl](cin = 肉桂基)Pd(II)–NHC 催化剂允许非常广泛的交叉偶联范围,以提供有价值的联芳基和异联联芳基吡啶,这些吡啶在医药中无处不在化学和农业化学研究。整个过程利用具有 N-C 活化作用的吡啶的 Chichibabin C-H 胺化作用来实现 2-吡啶基问题的有吸引力的策略。介绍了该方法在发现强效农用化学品中的实用性。考虑到 2-吡啶的重要性和 N-C 活化方法的多功能性,我们预计这种新的 C-H/N-C 活化策略将得到广泛应用。