Why does amino groups get acylated with acetic anhydride but not the hydroxy group? Thank you!
Sorry forgot to say this is in paracetamol. Why does the hydroxy gruop get acylated in aspirin but not paracetamol?
The aromatic amine group is much more nucleophilic than the aromatic alcohol. This follows from the basicity of the amine. If only one equivalent of acetic anhydride is used, the amine group will be isolated preferentially. However, if two equivalents of acetic anhydride are used, and the reaction pushed, the diacylated product can be obtained.
June 30th, 2008 at 12:15 pm
The aromatic amine group is much more nucleophilic than the aromatic alcohol. This follows from the basicity of the amine. If only one equivalent of acetic anhydride is used, the amine group will be isolated preferentially. However, if two equivalents of acetic anhydride are used, and the reaction pushed, the diacylated product can be obtained.