Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410082, China.
Angew Chem Int Ed Engl. 2016 Dec 19;55(51):15783-15786. doi: 10.1002/anie.201608371. Epub 2016 Nov 22.
An N-heterocyclic carbene (NHC) catalyzed dihalomethylenation of enals is described. It is a rare example of merging NHC catalysis with single-electron chemistry, a challenging topic with limited previous success. The versatile carbon-centered trihalomethyl radicals have been demonstrated, for the first time, to be compatible with an NHC-bound intermediate, thus leading to efficient and regioselective intermolecular C-C bond formation. The mild process provides straightforward access to unsaturated δ,δ-dihalo esters.
本文描述了 N-杂环卡宾（NHC）催化的烯醛二卤亚甲基化反应。这是 NHC 催化与单电子化学融合的罕见实例，是一个具有挑战性的课题，之前的成功案例有限。本文首次证明，多功能的碳中心三卤甲基自由基与 NHC 结合的中间体相容，从而导致高效和区域选择性的分子间 C-C 键形成。该温和的过程为不饱和 δ,δ-二卤代酯提供了直接的合成途径。
