Researches On The Bromination Of Acetophenone Compounds Using Succinimide/NaBrO₃/NaHSO₃ In Water Medium

?-Bromoacetophenone compound is an important drug intermediate.In this dissertation,we have presented a one-pot tandem bromination of acetophenones using succinimide/NaBrO3/NaHSO3 in water and synthesis of 2-aminothiazole derivatives from a-bromoacetophenones with thioureas.The described method supplied a green synthetic strategy to prepare a-bromoacetophenones and 2-aminothiazoles with good academic signification and application value.This paper includes two elements:1)Synthesis of a-bromoacetophenone compoundsThe one-pot tandem bromination of acetophenones using succinimide/NaBr03/NaHS03 to prepare a-bromoacetophenone derivatives in water was presented.The reaction conditions were optimized:acetophenone(4 mmol),n(succinimide):n(NaBr03):n(NaHS03)=1:3:3,25 mol%of TsOH,80 ?,The described method was easy for operation and pollution-free.The scope of the bromination was then studied.We have found that electron-donating as well as electronwithdrawing substituents on the beunzene ring are well accommodated.The yields of acetophenones containing an electron-donating group on the benzene ring are higher.2)Synthesis of 2-aminothiazole derivativesWe found that the reaction of a-bromoacetophenones with thioureas in the presence of NaHSO4 in aqueous media gave 2-aminothiazole derivatives in good to excellent yields.The reaction time,the type and amount of catalyst in this reaction were discussed.Various substituted aromatic ketones were also investigated.