Debrominations of vic-dibromides with diorganotellurides.: 3.: Rate constants, Eyring and Arrhenius activation parameters, and mechanistic implications

In summary, the bromination of olefins and subsequent debrominations of the resulting vic-dihalides offer a means for protection of the carbon-carbon double bond in synthesis. With strongly nucleophilc debrominating agents such as iodide and and, perhaps, aryltelluride anions, debrominations of vic- dibromides are initiated by nucleophilic attack at one bromine. With less nucleophilic debrominating agents such as dihexyltelluride (1), the propensity of the vic-dibromide to form bromonium ion intermediates determines relative reactivity. The divergence in mechanistic paths should permit the selective protection/deprotection of olefins with different substitution patterns.