PIDA mediated oxidative annulation of aryl methyl ketones: a facile approach for the chemoselective synthesis of 5-substituted oxazoles

Abstract

We have developed a simple and efficient protocol for the chemoselective synthesis of 5-substituted oxazoles via oxidative annulation of substituted acetophenones with NH₄OAc and DMSO using PIDA as an effective oxidant. NH₄OAc and DMSO act as less toxic one nitrogen and one carbon synthons, respectively. It is a metal-free, step and atom economical approach with good functional group tolerance and chemoselectivity.