Synthesis of γ-Azido-β-ureido Ketones and Their Transformation into Functionalized Pyrrolines and Pyrroles via Staudinger/aza-Wittig Reaction
作者:Anastasia A. Fesenko、Anatoly D. Shutalev
DOI:10.1021/jo302724y
日期:2013.2.1
The synthesis includes three-component condensation of acetals of 2-azidoaldehydes with urea or methylurea and p-toluenesulfinic acid in aqueous formic acid followed by reaction of the obtained N-[(2-azido-1-tosyl)alkyl]ureas with sodium enolates of α-functionalized ketones. The azido ketones or their cyclic isomers are transformed into ureido-substituted Δ1- or/and Δ2-pyrrolines via Staudinger/aza-Wittig
已开发出一种简单的两步程序,可生成γ-叠氮基-β-脲基酮或/和它们的环状异构体6-(1-叠氮基烷基)-4-羟基六氢嘧啶-2-酮。合成包括2-叠氮基醛的缩醛与脲或甲基脲和对甲苯磺酸在甲酸水溶液中的三组分缩合,然后使获得的N -[(2-叠氮基-1-甲苯基)烷基]脲与烯醇钠反应。 α-官能化酮的种类 叠氮基酮或其环状异构体被转化为脲基取代的Δ 1 -或/和Δ 2通过施陶丁格/氮杂Wittig反应通过PPH促进-pyrrolines 3。将获得的吡咯啉转化为3官能化的1 H-通过在酸性条件下消除尿素来形成-吡咯。还已经开发了从N -[(2-叠氮基-1-甲苯基)烷基]脲或γ-叠氮基-β-脲基酮开始的1 H-吡咯的方便的一锅合成。