The Hive > Stimulants
Failed Birch - Why?
dwarfer:
You have no hydrogen source in your reaction scheme.
You have to use either the HCl salt of pseudoephedrine
or an alcohol (anhydrous,
so take IPA or methylalcohol, dry!)
But using the HCl salt is better and easier.
--- End quote ---
;D (inside joke, huh Orge??)
1 red-headed bat will handle 7 to 8 grams
of fake:
but if there ain't no hydrogen around
it's not going to work:
and if I recall, theoretically, Li can reduce
toluene to something you don't want:
so don't use it until the blue is gone.
To bad about that search engine's apparently not working
on your end of the 'net.. :)
Xavl2:
Ok, swim has used search engine extensivelly and has never seen anything that would suggest toluene gets reduced to anything or that an extra hydrogen source is needed as in the HI reductions. Can someone write in full ALL reactions that occur during a birch please?
May swim attact everyone's attention to this article:
https://www.thevespiary.org/rhodium/Rhodium/chemistry/birch.pseudo.html
The article goes to explain in detail how the writer and his associates have reduced pseudo freebase to meth in a birch reaction by dissolving lithium in ammonia adding a preaddition toluene with freebase dissolved in it and then adding solid freebase so meth freebase goes straight into toluene. The guy sounds very knowledgeable and is obviously very familiar with the work of Eulesius and Fester which again gave him more credibility in swim's eyes.
Another article describes freebase addition in THF.
https://www.thevespiary.org/rhodium/Rhodium/chemistry/birch.reduction.html
Reference: From Ely & McGarth J Forensic Sci 35, 720-3 (1990)
Someone in swims neck of the woods just empties same amount of ammonia as there is of toluene with freebase, chucks lithium in and dumps toluene in and watches the whole thing bubble away and then gets at least a semi-decent product out of it considering freebase wasn't cleaned that well, nothing is measured and so forth.
WizardX:
maj states...
However I beleive the toluene actually 'quenched' your reaction. Thus not reduceding your ephedrine to methamphetamine.
--- End quote ---
Correct!
Use the ephedrine in the freebase form that has been dried azeotropically. Ephedrine forms a hydrate with water. Eg. Ephedrine. 1/2 H2O
Add anhydrous ephedrine (sold form) to your NH3/Li.
All these solvents form azeotropes with water @ 760 mmHg.
Example. CHCl3 Trichloromethane forms an azeotrope with water @ 56.1 oC.
CHCl3 Trichloromethane 56.1
CH2O2 Formic acid 107.2
CH3NO2 Nitromethane 83.6
CS2 Carbon disulfide 42.6
C2H3N Acetonitrile 76.5
C2H5NO2 Nitroethane 87.2
C2H6O Ethanol 78.2
C4H8O2 Ethyl acetate 70.4
C4H10O 1-Butanol 92.7
C4H10O 2-Butanol 87
C5H5N Pyridine 93.6
C5H11N Piperidine 92.8
C5H12 Pentane 34.6
C6H5Cl Chlorobenzene 90.2
C6H6 Benzene 69.3
C6H6O Phenol 99.5
C6H10 Cyclohexene 70.8
C6H12 Cyclohexane 69.5
C6H14 Hexane 61.6
C7H8 Toluene 84.1
C7H16 Heptane 79.2
C8H10 1,3-Dimethylbenzene 92
C8H10 Ethylbenzene 92
C8H18 Octane 89.6
C8H18O Dibutyl ether 92.9
Xavl2:
Ok, dug up are equations from TFSE written by chemguy 4 or 5 years back:
"It is really some what difficult to write out in text form but I will attempt.
a) Li (or any alkali metal) + NH3 (or other sutable solvent) --> Li(+) + e(-) (the solvated electron) + NH3
b) C6H5-CHOH-CH(NHCH3)-CH3 + 2 e(-) --> 1,4-( - )-C6H5-CHOH-CH(NHCH3)-CH3 [or the 2,5- it doesn't matter]
c) 1,4-( - )-C6H5-CHOH-CH(NHCH3)-CH3 + 2 Li(+) --> 4-( Li )-C6H5=CH-CH(NHCH3)-CH3 + LiOH
d) H2O (or any proton donor) + 4-(Li)-C6H5=CH-CH(NHCH3)-CH3 --> LiOH + 4-(H)-C6H5=CH-CH(NHCH3)-CH3
e) 4-(H)-C6H5=CH-CH(NHCH3)-CH3 --{tauterization (sp?)}--> C6H5-CH2-CH(NHCH3)-CH3"
So ok, swim is a moron and it should have been obvious that the H has to come from somewhere. In the post mentioned above https://www.thevespiary.org/rhodium/Rhodium/chemistry/birch.pseudo.html, the guys doing it quenches the reaction with water in the end, so that's where the proton comes from I guess.
Swim will attempt next either a water addition to the blue after 15 min of stirring or dripping suzy dissolved in MeOH into the blue untill blue is gone. More lithium may be added if more MeOH with freebase remains.
Any comments?
Xavl2:
WizardX: as much as swim agrees with you, swim doesn't think that was the problem since the solution remained blue till the end, so there were plenty of electrons to go around.
Swim obviously completelly ommited the hydrogen source needed to replace the OH group on the susy. Swim has read many a post instructing to "quench" the reaction with water however never realised that the quenching process actually supplies the needed hydrogen to complete the methamphetamine as stated by the above equations.
Swim heard and read of many using toluene as the solvent to add suzy in, but obviously addition of H2O or ice cubes supplies the needed proton to make MA.
Is swim's logic correct?
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