Synthesis of substituted imidazolines by an Ugi/Staudinger/aza-Wittig sequence
作者:Sebastian J. Welsch、Michael Umkehrer、Cedric Kalinski、Günther Ross、Christoph Burdack、Jürgen Kolb、Martina Wild、Anja Ehrlich、Ludger A. Wessjohann
DOI:10.1016/j.tetlet.2015.01.043
日期:2015.2
A series of 2-(acetamide-2-yl)-imidazolines (II) with 5 points of diversity were prepared by an Ugi-4CR–Staudinger–aza-Wittig-sequence starting from simple azidoalkylamines. The intramolecular aza-Wittig cyclization between the iminophosphane and the tertiary amide of the Ugi product (I) was effected by short microwave irradiation. Competitive cyclization to the secondary amide was not relevant, however