Sonochemical bromination of acetophenones using p-toluenesulfonic acid-N-bromosuccinimide.
Substituted acetophenones react with N-bromosuccinimide (NBS) and p-toluenesulfonic acid (p-TsOH) in the presence of ultrasound in methanol at 35 +/- 2 degrees C to give alpha-bromoacetophenones in high yield. In the absence of ultrasound the reaction takes place at the boiling point of methanol (65 degrees C) and takes longer time. The reaction does not take place in the absence of p-TsOH thermally or sonically. However the reaction is possible under photochemical conditions in the absence of p-TsOH. The best solvent for the reaction was found to be methanol.
Adhikari
M V
MV
Organic Chemistry Research Laboratory, Division of Applied Chemistry, Department of Chemical Technology, University of Mumbai, Matunga, Mumbai-400 019, India.
Samant
S D
SD
D000098:Acetophenones / Q000737:chemistry*; D001557:Benzenesulfonates / Q000737:chemistry*; D001965:Bromides; D001974:Bromosuccinimide / Q000737:chemistry*; D007700:Kinetics; D014465:Ultrasonics
D000098:Acetophenones; D001557:Benzenesulfonates; D001965:Bromides; D001974:Bromosuccinimide; C029501:4-toluenesulfonic acid