Selective Monobromination Research Articles

Ultrasound Promoted Bromination of Activated Arenes withN-Bromosuccinimide

Abstract Ultrasound irradiation has resulted in the selective monobromination of activated aromatics with N-Bromosuccinimide (NBS) in carbon tetrachloride at ambient conditions in the absence of any added catalyst.

The selective monobromination of methane with mixtures of bromine and chlorine

AbstractThe reaction between methane and mixtures of bromine and chlorine was investigated.Maximum conversions of bromine into methyl bromide of 63% were obtained; this yield can be improved by further increasing the methane: halogen ratio.When ethane was used instead of methane, higher yields (up to 75%) and a higher selectivity towards monobromination were found.The results strongly suggest a branched free radical chain reaction. The rate determining step is the attack of a chlorine radical on the hydrocarbon.These conclusions are supported by approximate calculations, based upon the proposed reaction mechanism.