BIOL 3305 Lecture Notes - Lecture 30: Hydrazine, Hydroxylamine, Hemiaminal
Document Summary
The carbinolamine has its oxygen protonated, and then water acts as the good leaving group. This acid catalyzed dehydration creates the double bond, and the last step is the removal of the proton to produce the neutral amine product. The ph of the reaction mixture is crucial to successful formation of imines. The ph must be acidic to promote the dehydration step, yet if the mixture is too acidic, then the reacting amine will be protonated, and therefore un- nucleophilic, and this should inhibit the first step. The best ph for imine formation is around 4. 5. Aldehydes and ketones also condense with other ammonia derivatives, such as hydroxylamine and hydrazines. Generally these reactions are better than the analogous amine reactions (i. e. give superior yields). Oximes are produced when hydroxylamines are reacted with aldehydes and ketones. Hydrazones are produced through reaction of hydrazines with aldehydes and ketones.
