So would the addition of acetic anhydride to an amine be acylation? (Yes. It is actually acyl nucleophilic substitution, because half of the anhydride molecule leaves. - GS). Also are there the same issues with acylation as there are with alkylation when trying to make a primary amine or not because acylation is substitution? (No. The C=O group in an acyl blocks the lone electron pair on nitrogen from the second acylation. That is why acylation can be used as a get-around way to avoid the issue with multiple alkylations. Example - Gabriel synthesis. - GS).