Shu Chao, Mega Riccardo S, Andreassen Björn J, Noble Adam, Aggarwal Varinder K
School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Angew Chem Int Ed Engl. 2018 Nov 19;57(47):15430-15434. doi: 10.1002/anie.201808598. Epub 2018 Oct 25.
Herein, we describe the development of a photoredox-catalyzed decarboxylative radical addition-polar cyclization cascade approach to functionalized cyclopropanes. Reductive termination of radical-polar crossover reactions between aliphatic carboxylic acids and electron-deficient alkenes yielded carbanion intermediates that were intercepted in intramolecular alkylations with alkyl chlorides appended to the alkene substrate. The mild conditions, which make use of a readily available organic photocatalyst and visible light, were demonstrated to be amenable to a broad range of structurally complex carboxylic acids and a wide variety of chloroalkyl alkenes, demonstrating exquisite functional group tolerance.
在此，我们描述了一种光氧化还原催化的脱羧自由基加成-极性环化串联方法，用于合成官能化环丙烷。脂肪族羧酸与缺电子烯烃之间的自由基-极性交叉反应的还原终止产生了碳负离子中间体，这些中间体在分子内烷基化反应中被截获，该反应中烯烃底物上连接有烷基氯。利用易于获得的有机光催化剂和可见光的温和条件，已证明适用于多种结构复杂的羧酸和各种各样的氯烷基烯烃，显示出优异的官能团耐受性。
