Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
Org Biomol Chem. 2021 Nov 3;19(42):9172-9176. doi: 10.1039/d1ob01733k.
A mild photoredox-catalyzed intramolecular cyclopropanation of alkenes with α-bromo-β-keto esters in an aqueous medium was developed. The sequential reaction process comprising the intramolecular radical addition of α-bromo-β-keto esters to olefins under photoredox catalysis, and subsequent cyclization to form cyclopropane proceeds in one-pot under exceptionally mild conditions at room temperature in the presence of 2,6-lutidine. A broad range of substrates consisting of various alkenes and both base- and acid-sensitive functionalized esters were feasible under the reaction conditions, resulting in a wide range of functionalized bicyclic cyclopropanes.
发展了一种在水相介质中，通过光氧化还原催化实现α-溴代-β-酮酯与烯烃的温和分子内环丙烷化反应。在 2,6- 二甲基吡啶存在下，该串联反应过程包括光氧化还原催化下α-溴代-β-酮酯对烯烃的分子内自由基加成，以及随后的环化形成环丙烷，在室温下极其温和的条件下一锅法进行。在反应条件下，各种烯烃和酸碱敏感官能化酯组成的广泛的底物都是可行的，得到了广泛的功能化双环环丙烷产物。
