3H-Pyrroles, Alkylidene-Pyrrolines and Functionalized Pyrrolidines by Radical Cyclization of β-Allenyliminyl Radicals
作者:Michaël Depature、Jacques Grimaldi、Jacques Hatem
DOI:10.1002/1099-0690(200103)2001:5<941::aid-ejoc941>3.0.co;2-e
日期:2001.3
reaction of allene-tethered dithiosemicarbazides 4 is a convenient method for the preparation of five-membered unsaturated nitrogen heterocycles. The sulfur-directed intermolecular attack of the tin radical at the semicarbazide moiety leads to an allene-tethered iminyl radical, which then undergoes a 5-exo-dig cyclization leading to both the 3H-pyrroles 5 and the alkylidene pyrrolines 6; thermal isomerization
在这项工作中,我们表明氢化锡介导的丙二烯系二氨基硫脲 4 的反应是制备五元不饱和氮杂环的便捷方法。氨基脲部分的锡自由基的硫导向分子间攻击导致丙二烯系亚胺基自由基,然后进行 5-exo-dig 环化,导致 3H-吡咯 5 和亚烷基吡咯啉 6;在某些情况下会发生 5 到 6 的热异构化。