[hz862000]

Hi, I was just wondering which of the two functional groups in p-aminophenol would react first with acetic anhydride and why.  I know that it is the amino group, but I'm not sure why.  Also, I need to know what purpose water serves in the reaction.  I was thinking that it reacts with acetic anhydride to form two carboxylic acids, and then it activates one of them to turn it into a better electrophile.  I'm not sure if it is involved with the amino group in any way.  Please let me know, and thanks.