It seemed highly unlikely to Antoncho that such an obvious idea has never been mentioned, so he UTFSE'd his ass off, but - to no avail.
Say, what do you think, is it possible to use anything else than GAA in bromination of a ring-substituted phenethylamine? (well, you guessed it right, i mean 2C-H, of course).
The point is: bromination the "usual way" gives a low yield, with the amt of the final product being roughly the same that the used freebase - the theoretical yield being twice as much!
So... Obviously, the bromination conditions are way too vigorous for the amine function. The most obvious solution for this would bee to carry out this rxn at a lower temp. And, indeed, Hest's recent account on chlorination of 2,5-DMA at -78 C, the yield being 70%+ , suggests that it can and should bee done.
Unfortunately, GAA solidifies at 16 C.
So, does anyone see any visible obstacles to performing the bromination of 2C-H in CHCl3 at a freezer temperature, for whatever time it will take? Has anybee, maybee, actually done this or something similar?
Another interesting possibility would bee to use dioxane dibromide, which is highly selective and mild brominaiton agent - see for example its use in bromination of benzenes ond acetone (BTW, can anyone explain me, why it's so selective? Is it only due to the fact of Br2 being unable to form free radicals or some other effect?)
Please, dear bees, share whatever you have in mind
Antoncho