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 delivery of both bromine atoms from Br2 to...

A decade of lessons in the activation of ArIL2 species

“…For a method using I( iii ) in the rapid bromination of deactivated arenes we recently found that p -NO 2 -C 6 H 4 -IL 2 systems, where L is triflate or trifluoroacetate in concert with Br 2 enables the bromination of unreactive species including –CF 3 and – p -NO 2 substituted arenes ( Scheme 21 ). 96 The active intermediate is unknown at present but appears to arise from Lewis acidic activation of Br 2 by I(III) and then reoxidation of the HBr by-product by I(III), which is supported by the bromination of 2 equivalents of substrate per Br 2 and I(III) equivalent, achieving full consumption of the bromine. The advantage is brominations of deactivated arenes can be carried out rapidly at room temperature in organic solvent, whereas other methods for deactivated species require harsh media such as H 2 SO 4 solvent.…”