Department of Chemistry, York University 4700 Keele Street, Toronto M3J 1P3, Canada.
Lilly Research Laboratories, a Division of Eli Lilly and Company , Indianapolis, Indiana 46285, United States.
J Am Chem Soc. 2017 Dec 27;139(51):18436-18439. doi: 10.1021/jacs.7b09488. Epub 2017 Dec 15.
Boron-derived Lewis acids have been shown to effectively promote the coupling of amide nucleophiles to a wide variety of oxidative addition partners using Pd-NHC catalysts. Through a combination of NMR spectroscopy and control studies with and without oxygen and radical scavengers, we propose that boron-imidates form under the basic reaction conditions that aid coordination of nitrogen to Pd(II), which is rate limiting, and directly delivers the intermediate for reductive elimination.
硼衍生的路易斯酸已被证明可以有效地使用 Pd-NHC 催化剂促进酰胺亲核试剂与各种氧化加成试剂的偶联。通过 NMR 光谱和有/无氧以及自由基清除剂的对照研究，我们提出在有助于氮与 Pd(II)配位的碱性反应条件下形成硼-亚氨酸酯，这是速率限制步骤，并且直接提供了用于还原消除的中间体。
