Atropos (Stranger / Eraser)
11-20-02 02:15
No 381417
      Amination of haloalkanes via PTC, a question.  Bookmark   

It's well established that the amination of haloalkanes gives poor yields, with ammonia being a poorer nucleophile than methylamine.

Is it possible that methylamine or ammonia could be used in a dual phase reaction with a quaternary ammonium salt used as a phase transfer catalyst? 

In a dual solvent reaction, azides give relatively poor yields for secondary haloalkenes, but it does work.  Using a PTC these yields are significantly higher. 

Could a PTC be used to increase yields with something such as methylamine HCL, since it has ionic character?

The side products of both reactions are primarily eliminations, so if the PTC helps to reduce the elimination side reaction in the azide scenario, could it also serve to do the same thing in the direct amination?
 
 
 
 
    Rhodium
(Chief Bee)
11-20-02 02:44
No 381433
      From bromosafrole to MDA & MDMA  Bookmark   

Regarding the use of a PTC: It might be helpful, I think that Drone#342 posted a suggested bromosafrole/methylamine/PTC reaction once.

However, you still have the unavoidable problem of multiple alkylation of the methylamine, an impurity that won't go away unless you do a fractional distillation of the product freebase, followed by recrystallization of the final salt.

If you want to go from bromosafrole -> MDA, then use the azide route: ../rhodium/chemistry /mda.azide.html

If you want to go from bromosafrole -> MDMA, then first turn it to MDP2P, then aminate: ../rhodium/chemistry /halide.carbonyl.html
 
 
 
 
    Atropos
(Stranger / Eraser)
11-20-02 03:11
No 381443
      Hmmm...  Bookmark   

I have read both of those pages by the way, as well as most of your site.  I am very interested in all the methods that avoid the ketone as the intermediate...  Why you may ask?  Hell if I know...

I didn't know that about the multiple alkylation of methylamine.  I will look into that, as well as try to dredge up the Good Reverands post.

Always eager for the input...