Ketones and aldehydes react with primary amines to give imines. They react with secondar...

Ketones and aldehydes react with primary amines to give imines. They react with secondary amines to give enamines (vinyl amines).

(a) For review, propose a mechanism for the following formation of an imine.

(b) Now give a mechanism for a similar reaction that gives an enamine.

(c) Explain why the reaction with the secondary amine gives an enamine rather than an imine.