Ultrasound promoted acetylation of alcohols in room temperature ionic liquid under ambient conditions

The O-acetylation of alcohols with acetic anhydride to the corresponding esters has been achieved in excellent isolated yields in short reaction time at ambient conditions under ultrasonic irradiation in the absence of any added catalyst using a room temperature ionic liquid as the medium as well as a promoter for the reaction. The products could be isolated by distillation or selective extraction from the non-volatile ionic liquid, which could be recycled giving rise to a process with minimal waste.