Remote Radical Desaturation of Unactivated C−H Bonds in Amides
作者:Yong Xia、Kalipada Jana、Armido Studer
DOI:10.1002/chem.202103509
日期:2021.12
A copper-catalyzed/silver-promoted desaturation method is described which allows the regioselective conversion of various unactivated N-alkylamides at remote sites to the corresponding N-alkenylamides via N-centred radical mediated 1,5 hydrogen atom transfer, metal-mediated oxidation and deprotonation. The transformation shows good functional group tolerance and can be used for late-stage desaturation
描述了铜催化/银促进的去饱和方法,该方法允许通过以 N 为中心的自由基介导的 1,5 氢原子转移、金属介导的氧化和去质子化。该转化表现出良好的官能团耐受性,可用于药物衍生物和生物学上更相关的化合物的后期去饱和。
5-<i>Exo</i> versus 6-<i>Endo</i> Cyclization of Primary Aminyl Radicals: An Experimental and Theoretical Investigation
作者:Feng Liu、Kun Liu、Xinting Yuan、Chaozhong Li
DOI:10.1021/jo7015967
日期:2007.12.1
The cyclization of neutral primary pent-4-enylaminyl radicals was investigated experimentally and theoretically. Unlike the corresponding secondary aminyl radicals, primary pent-4-enylaminyl radicals underwent efficient cyclization to afford the pyrrolidine and/or piperidine products in good to high yields. While the simple pent-4-enylaminyl radical gave predominately the 5-exo, cyclization product, 4-chloropent-4-enylarninyl radicals led to the formation of the corresponding 6-endo cyclization products in excellent regioselectivity. Theoretical calculations revealed that the 5-exo cyclization rate of primary aminyl radicals is about 3-4 orders of magnitude higher than that of secondary aminyl radicals.