Reaction of [(Z)-1-bromo-1-alkenyl]dialkylboranes with N-halogeno compound in THF–DMF: a novel synthesis of 1,2-disubstituted (E)-vinyl bromides

DMF-induced reaction of [(Z)-1-bromo-1-alkenyl]dialkylboranes with an N-halogeno compound results in 1,2-migration of an alkyl group from the dialkylboryl group to the α-carbon atom without elimination of the bromine atom, followed by β-elimination to provide 1,2-disubstituted (E)-vinyl bromides stereoselectively in good yields.