Electrophilic activation of molecular bromine mediated by I(iii)

Abstract

In pursuit of a genuine bromo-λ³-iodane, it has been found that the combination of Br₂ and electron deficient λ³-iodanes can result in the delivery of both bromine atoms from Br₂ to a range of aryl substrates, some highly deactivated. These brominations occur rapidly in common chlorinated solvents at room temperature and can be achieved with the catalytic activation of commercially available PhI(OAc)₂ and PhI(OTFA)₂. para-NO₂ substituted derivatives are employed to direct bromination towards more deactivated substrates. The mechanism of Br₂ activation is discussed with insights being made, however it remains unclear.