Synthesis of substituted oxazoles from enamides†
Abstract
Annulation of enamides into 2,5- and 2,4,5-substituted oxazoles by NBS/Me2S in the presence of mild base has been achieved. The reaction conditions are simple and tolerant to a wide variety of substituents including both electron-donating and withdrawing groups to produce oxazoles in one-pot without further purification of the intermediate.