Abstract
Treatment of
N
-bromosuccinimide (NBS) with (carboethoxymethylene) triphenylphosphorane (
1
) in CH
2
Cl
2
followed by the addition of an alcohol in the presence of manganese dioxide under ultrasonic irradiation constitutes a stereoselective one-pot procedure for the preparation of
Z
-configured α–bromo-α,β-unsaturated esters in good to excellent yield.