[adamr]

I have a few questions I've been wondering about regarding an experiment that was performed in an Organic Chemistry lab. It was a reductive amination to prepare N-(P-Tolyl)piperonylamine.

We used an acid: acetic acid. I was thinking about why we used it and I think it's because it helps with the dehydration, yet I was wondering: would this reaction still work without the acid? Also we only used 2 drops of acetic acid and I was wondering what really influences how many drops we use?

CH2Cl2 was used as the solvent in this experiment, does anyone know why this is a  good solvent for reductive amination reactions like this? Also, I found it interesting that the CH2Cl2 layer was extracted 2 x with water, usually it seems to be the other way around. Does anyone know why this is?

These are some questions I have about this experiment that was performed. If anyone can come up with good explanations to my questions, it would help me greatly in understanding this experiment better!

[willch]

Try http://www.chemrefer.com/3555863.html.

Post back here on chemical forums to tell me if it helped.

[adamr]

Thanks for your help. It turns out that link did not really help at all in answering my questions, but thanks for trying. I really do appreciate that you tried to help. Thanks!

[willch]

Thanks for the feedback. Hopefully I'll give better answers in future! Hope you find what you're looking for.

[movies]

Acids are usually used in some small amount in reductive aminations in order to catalyze the formation of the iminium species that is reduced to the amine.  Draw out a detailed mechanism, and you should find that a proton will help out in the first steps.

As for the solvent, that's not as critical.  CH₂Cl₂ is a generally good solvent for lots of reactions, but I don't think it plays any special role here.  As for the workup, you probably washed the organic layer with water, not extracted (there is a subtle difference!)  This wash would get rid of any acid or borane side products.  If you did really extract into the aqueous layer, that would be because the amine happened to be very soluble in water.