Practical oxazole synthesis mediated by iodine from α-bromoketones and benzylamine derivatives

The reagent system of I-2/K2CO3 could efficiently promote the oxazole synthesis from alpha-bromoketones and benzylamine derivatives in DMF. This method was not only suitable for 2,5-diaryl oxazole synthesis but also for 2,4,5-trisubstituted oxazole and 5-alkyl/alkenyl oxazole synthesis. Furthermore, this method was successfully applied to a one-step synthesis of a natural product halfordinol in 62% yield.