catalysis is an efficient process for the alkylation of diverse organic compounds via the generation of alkyl radicals from alkyl bromides and iodides. However, the generation of alkyl radicals from more stable alkyl chlorides remains challenging. Herein, we demonstrate the excited-state palladium-catalyzed synthesis of oxindoles and isoquinolinediones via alkylation/annulation reaction by overcoming
Construction of Quaternary Carbon Center via NHC Catalysis Initiated by an Intermolecular Heck-Type Alkyl Radical Addition
作者:Lanjun Su、Huan Sun、Jikai Liu、Chengming Wang
DOI:10.1021/acs.orglett.1c01400
日期:2021.6.18
A quaternary carbon center containing an oxindole motif is constructed via NHC-catalyzed transition-metal and aldehyde-free intermolecular Heck-type alkyl radical addition initiated annulation. This redox-neutral protocol also features a simple procedure, broad substrate scope, good functional group tolerance and could be smoothly amplified to a gram scale. The mechanism study shows that the reaction
含有羟吲哚基序的季碳中心是通过 NHC 催化的过渡金属和无醛分子间 Heck 型烷基自由基加成引发的环化构建的。这种氧化还原中性方案还具有程序简单、底物范围广、官能团耐受性好并且可以顺利放大到克级的特点。机理研究表明,该反应可能经历了两次 SET 过程,其中涉及 NHC 自由基阳离子中间体。
Radical cascade cyanomethylation of activated alkenes to construct cyano substituted oxindoles
作者:Juan Li、Zhigang Wang、Ningjie Wu、Ge Gao、Jingsong You
DOI:10.1039/c4cc07667b
日期:——
cyanomethyl radical was easily generated from acetonitrile by using DTBP, which was applied to a cascadealkene addition and cyclization reaction to construct useful oxindole derivatives. This protocol features simple manipulation, cheap reagents and a broad substrate scope. In addition, nitro substituted oxindoles were also synthesized for the first time.