The Vespiary

The Hive => Chemistry Discourse => Topic started by: ropoctl on August 14, 2003, 03:33:00 AM

Title: Alpha-Dimethyl-Phenethylamines?
Post by: ropoctl on August 14, 2003, 03:33:00 AM

(https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000453444-file_uoww.gif)
Is anything known about this species?

Title: It's called Phentermine.
Post by: moo on August 14, 2003, 03:38:00 AM

It's called Phentermine.

Title: Sorry, Don't think I coulda figured that from TSFE
Post by: ropoctl on August 14, 2003, 04:29:00 AM

I just thought phentermine looked like
(https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000453444-file_g1nu.gif)
Thanks, now I know what to UTSFE for.

Title: Phentermine
Post by: roger2003 on August 14, 2003, 10:19:00 AM

Monograph Number:  7346
Title:  Phentermine
CAS Registry Number:  122-09-8
CAS Name:  a,a-Dimethylbenzeneethanamine
Additional Names:  a,a-dimethylphenethylamine;  phenyl-tert-butylamine;  a-benzylisopropylamine
Molecular Formula:  C10H15N
Molecular Weight:  149.23. 
Percent Composition:  C 80.48%, H 10.13%, N 9.39%
Literature References:  Prepn:  Shelton, Van Campen, US 2408345 (1946 to Wm. S. Merrell); Abell et al., US 2590079 (1952 to Wyeth).
Properties:  Oily liquid.  bp750 205°; bp21 100°.
Boiling point:  bp750 205°; bp21 100°

Title: The comfort of using patent tags...
Post by: Vitus_Verdegast on August 14, 2003, 03:40:00 PM

... to have instant access to these mentioned patents, which might interest some people.


So I'll add them here:

Shelton, Van Campen,

Patent US2408345 (http://l2.espacenet.com/dips/viewer?PN=US2408345&CY=gb&LG=en&DB=EPD)

(1946 to Wm. S. Merrell)
Abell et al.,

Patent US2590079 (http://l2.espacenet.com/dips/viewer?PN=US2590079&CY=gb&LG=en&DB=EPD)

(1952 to Wyeth).

Title: I know about this stuff, but sorry...
Post by: Tricky on August 14, 2003, 05:26:00 PM

...have no time to translate the post of Fomalhaut about the "simpliest synthesis" :) may bee some other russian bee will do it instead of me ...

Check out:

Post 441428 (missing)

(Fomalhaut: "Ôåíòåðìèí - ñàìûé ïðîñòîé ñòèìóëÿòîð.", Russian HyperLab)
Good luck!

Title: Phentermine
Post by: roger2003 on August 15, 2003, 02:48:00 AM

Phentermine from benzaldehyde and 2-nitropropane

JOC 37, 1861 (1972)

Title: Phentermine Synthesis
Post by: Rhodium on August 15, 2003, 03:12:00 AM

Reductive synthesis of (https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000453444-file_lwwo.gif),(https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000453444-file_lwwo.gif)-dimethylphenethylamine
Fritz H. Marquardt, Susan Edwards

J. Org. Chem. 37(11), 1861-1863 (1972) (https://www.thevespiary.org/rhodium/Rhodium/pdf/phentermine.synthesis.pdf)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/phentermine.synthesis.pdf)

Title: why is it neccasary to proceed via the ...
Post by: stratosphere on February 04, 2004, 11:57:00 PM

why is it neccasary to proceed via the nitro-alcohol?
it would seem to me that a simpler procedure would be to condense the nitronate ion onto a benzylhalide.
while there could be some reaction between the benzylhalide and the base, it would seem that this condition could be managed by combing the 1equiv of nitropropane, 1 equiv of KOH in the ethanol, allow the mixture to sit long enough for deprotonation to occur, and then slowly add in 1 equiv of benzylhalide.
to insure that all the presumably more expensive, 2-nitroprpane is consumed, one could then add for example 0.1equivs of KOH to the ethanol, and slowly drip in another 0.1 equivs of benzylhalide.
since the nitro group is located on a tert carbon, it would seem there would be little danger of the nitro-phentermine undergoing any side reactions.

Title: Ending up with benzaldehyde
Post by: Rhodium on February 05, 2004, 01:39:00 AM

This may be a side reaction:

Post 204795 (https://www.thevespiary.org/talk/index.php?topic=11640.msg20479500#msg20479500)

(obituary: "Arom. ald. synth", Novel Discourse)

Post 292292 (https://www.thevespiary.org/talk/index.php?topic=6447.msg29229200#msg29229200)

(lugh: "Halides to Carbonyls", Chemistry Discourse)

Title: that last article is interesting, it seems the
Post by: stratosphere on February 06, 2004, 08:07:00 PM

that last article is interesting, it seems the oxidation occurs via the formation of the nitro-ester, followed by its disportiation.
certainly using low temps would greatly slow the disporportation of the nitro-ester, but that would only help if the halide-->nitro-ester reaction is reversible since the alkalytion isn't
(i.e. the equilibrium constant for alkyl-halide + proponitrone<-->alkyl-proponitrone ester+ halide ion is not to large) , so perhaps using an aprotic solvent and a more nucleophilic halide (Br or even better I) could give adequete yields.
swim shall put this on his list of experiments worth doing.