Author Topic: phenethylamines from benzoic acids ?  (Read 2752 times)

0 Members and 1 Guest are viewing this topic.

xxxxx

  • Guest
phenethylamines from benzoic acids ?
« on: April 25, 2004, 12:13:00 AM »
a benzoic acid ester is condensed with NaOEt and diethyl malonate to form c6h5coch(cooet)2. a mannich reaction is performed with coh2 and nh3 to form c6h5coc(ch2nh2)(cooet)2.
sometimes a carbon monoxide moiety can be expelled by heating if it is adjacent to electron withdrawing groups such as cooet. would like to ask if this would occur with this compound and what temperature (160C?) would be required and yield. if carbonyl moiety is expelled then heating with sulfuric acid would remove cooet groups leaving phenethylamine.

Nicodem

  • Guest
Learn to count carbons?
« Reply #1 on: April 25, 2004, 10:59:00 AM »
You can't remove that carbonyl by heathing (this is not like -CO-COOH!). Only the ester groups can bee hydrolised and decarboxylated simultaneously at 90 - 100°C in aq. acid. And you can't make that Mannich bases with ammonia. Only dialkylamines give useful yield, ammonia gives a trialkylated Mannich base.


xxxxx

  • Guest
utility of alpha-keto ethyl benzene
« Reply #2 on: April 26, 2004, 06:27:00 PM »
would the compound c6h5coch3 result from the heating with acid? this might have some synthetic utulity.

Rhodium

  • Guest
malonic synthesis of acetophenone
« Reply #3 on: April 27, 2004, 02:05:00 AM »
Yes. That compound is called acetophenone, and its preparation via the acylation of diethyl malonate is described in the article linked in

Post 503140

(Rhodium: "P2P by acylation of diethyl malonate", Methods Discourse)



xxxxx

  • Guest
proposed process
« Reply #4 on: May 03, 2004, 06:56:00 PM »
1) ethyl benzoate condensed with ethyl acetate to form c6h5coch2cooc2h5. 2) reduce ketone to c6h5ch2ch2cooc2h5. 3)add ammonia in alcohol to form c6h5ch2ch2conh2. 4) react with hypochlorite to form c6h5ch2ch2nh2. would this process work or not? which steps might be most difficult/low yielding?

ning

  • Guest
Could you write more clearly?
« Reply #5 on: May 04, 2004, 01:32:00 AM »
And get beilstein or something.

1. This step should have a reference. Yields vary. Seems doable, but. Hm. You'd need a strong base, like NaOEt, unless the PTC Claisen condensation pans out.
Why not use acetonitrile instead? It already has the amine present.

2. Wolff-kishner or Clemmenson reduction. Got hydrazine?

3. Try using urea instead. UTFSE for Eleusis's methylamine FAQ, where they perform such an operation to make acetamide.

4. Hoffmann rearrangement. Doable. Yields ning has seen are in the ~50% region, depending very much on how activated the ring is to halogenation, one of the competing reactions.

Dude, format your posts better if you want people to read them!

The major advantage of your proposed scheme is that (if it works) it offers a route to substituted cathinones or their phenethylamine equivalents. (i.e. don't remove the ketone part)

Barring that, I imagine most bees who could rustle up the hydrazine and sodium ethoxide required for your idea could find some nitromethane and aluminum foil instead. Ah, well.