A highly selective and efficient acetylation of alcohols and amines with acetic anhydride using NaHSO4•SiO2 as a heterogeneous catalyst

Treatment of alcohols and amines (aliphatic and aromatic) with acetic anhydride at room temperature using NaHSO4 center dot SiO2 as a heterogeneous catalyst affords the corresponding acetates in excellent yields. The method is highly chemoselective-alcoholic hydroxyl group can be protected while phenolic hydroxyl group remains intact and the amine group can be acetylated in the presence of hydroxyl. Symmetrical diols produced only the monoacetates. The method has been applied for the preparation of venkatasin, a natural coumarino-lignan and of Baylis-Hillman acetates. (c) 2006 Elsevier B.V. All rights reserved.