Hypervalent iodine-mediated aminobromination of olefins in water

The PhI(OAc)2-catalyzed aminobromination of electron-deficient olefins has been achieved in pure water with TsNH2 and NBS as nitrogen and bromine sources, respectively. With a catalytic amount of PhI(OAc)2, various olefins including α,β-unsaturated ketones, cinnamates, and cinnamides could be aminobrominated efficiently, giving the vicinal bromoamines in good yields and high regio- and diastereoselectivities. Utilizing water as solvent was crucial to realize this aminobromination reaction catalytically. The regioselectivity for the aminobromination of styrenes under the present aqueous conditions was also dramatically improved.