Synthesis of Thiazolines by Copper Catalyzed Aminobromination of Thiohydroximic Acids

A copper catalyzed aminobromination of alkene tethered thiohydroximic acids is described, providing a rapid approach to unnatural thiazoline scaffolds not readily available via existing methods. Moderate to high yields of bromothiazolines are obtained with alkyl- and aryl-substituted thiohydroximic acid building blocks containing mono-, di-, and trisubstituted alkenes. The reaction provides high levels of 5-exo selectivity, and terminally monosubstituted alkenes result in predominant syn-diastereoselectivity.