Diastereoselective Photoredox-Catalyzed [3 + 2] Cycloadditions of <i>N</i>-Sulfonyl Cyclopropylamines with Electron-Deficient Olefins
作者:Dawn H. White、Adam Noble、Kevin I. Booker-Milburn、Varinder K. Aggarwal
DOI:10.1021/acs.orglett.1c00711
日期:2021.4.16
A highly diastereoselective, visible-light-induced [3 + 2] cycloaddition between N-sulfonyl cyclopropylamines and electron-deficient olefins is reported. The reactions proceed via the oxidation of a sulfonamide aza-anion by an organic photocatalyst to generate a nitrogen-centered radical. Strain-induced ring opening and intermolecular addition to the olefin generate an intermediate carbon-centered
报道了在N-磺酰基环丙胺和缺电子烯烃之间的高度非对映选择性,可见光诱导的[3 + 2]环加成反应。反应通过有机光催化剂氧化磺酰胺氮杂阴离子以产生氮中心自由基而进行。应变诱导的开环和向烯烃的分子间加成产生中间的以碳为中心的自由基,该自由基在5-exo环化之前被还原成阴离子。这使得具有非合成选择性的具有合成上有用的官能团的反式环戊烷的结构成为可能。