Selective 1,1- and 1,2-dibromination of phenylethanes in the presence of NaBr/NaBrO 3 /H 2 SO 4 as the bromination reagent.

Selective 1,1- and 1,2-dibromination of phenylethanes by simply adjusting the reaction conditions has been developed. Mixtures of NaBr/NaBrO 3 /H 2 SO 4 are employed as green bromination reagents, which can release Br 2 or BrOH in situ as required without polluting the environment. Both the resulting 1,1- and 1,2-dibromoethyl arenes can be easily transformed to phenylacetylenes via elimination under basic conditions, demonstrating great potential for industrial applications.