Readily switchable one-pot 5-exo-dig cyclization using a palladium catalyst
作者:Jaishree K. Mali、Balaram S. Takale、Vikas. N. Telvekar
DOI:10.1039/c6ra25857c
日期:——
A convenient, ligand-free, Pd(OAc)2-catalyzed one-pot reaction has been developed for the synthesis of oxazolines and oxazoles from easily available acid chlorides and propargylamine. The reaction pathways could be easily modulated to selectively obtain oxazolines or oxazoles by merely changing the additives. This method proceeds via in situ sequential nucleophilic addition/elimination reactions followed
From Propargylic Amides to Functionalized Oxazoles: Domino Gold Catalysis/Oxidation by Dioxygen
作者:A. Stephen K. Hashmi、Maria Camila Blanco Jaimes、Andreas M. Schuster、Frank Rominger
DOI:10.1021/jo301288w
日期:2012.8.3
5-disubstituted oxazoles from propargylic amides is reported. A series of propargylic amides were transformed to the corresponding alkylideneoxazolines by a gold(I) catalyst. The next step was an autoxidation to hydroperoxides bearing the heteroaromatic oxazoles. Experiments addressing the reaction mechanism reveal a radical pathway for this autoxidation process. The hydroperoxides could conveniently be converted