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Nicodem
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Addition of organolithium and Grignard compounds to nitroalkanes gives the nitronate nucleophilic addition product which on quenching with weak acid
yields the corresponding nitrone. See chapter 1.2.1.6 in Studies towards the stereoselective electrophilic amination of carbanions and references therein.
If you have a reference to support your claim I would like to see it (even though it would be the most idiotic synthesis of nitroethane ever, but who
cares about something as cheap as nitroethane anyways).
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solo
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Quote: | Originally posted by formyl
nitromethane can be alkylated via a dual deprotonation with 2 equiv n-butyllithium. once the second proton is removed, the most reactive site is at
carbon |
Can you please post the reference or was this a first hand experience, if so can you share the conditions and reaction parameters......solo
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Furch
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IIRC, the theory that Formyl is referring to is presented in the latest edition of March's. I don't have access to it right now, but if someone else
does, there will be references for sure
- Furch
\"Those who say do not know, those who know do not say.\" -Lao Tzu
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Matchheads
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I don't like any methylamine substitutes.
Nitroethane appears in a synthesis toward producing phenyacetone from benzaldehyde. How come nobody mentioned that? You can use substituted
benzaldehydes. The one for MDMA is called heliotropin. I believe this is called the Leukart reaction.
Yeah, it is that. Heliotropin is called piperonal. That's the better name. Totse says not to do the Leukart. I wonder is that exclusive to MD-P2P
or if regular P2P shouldn't be made that way either.
I don't really like P2P. It stinks far too much and boils at 216. They only use it to get MDMA. There isn't any dextrorotatory XTC then.
I don't know how to make it. I'd like someone who made it to post how. I know how to make ripping speed. I wouldn't want to go back to P2P. I
don't care anyway. Where's the non-drug, non-explosive chemistry in here? How about some silver, gold, and platinum schemes? How about a good
chrome plating recipe? How about a nice green anodize process?
The "Whole Drug Manufacturer's Catalog" had one starting from chlorotoluene, through a Grignard, to racemic methamphetamine, but someone said that was
backward. There was a step where you prepare an imine from acetaldehyde and methylamine. Now, in the Grignard reaction,...
I looked it up on Answers.com. I can't see where RMgX goes to R-C(R1)NH(R2). I took a Vicodin. If its only useful for scary-substituted benzenes
thence to a P2P the one we want is MD toluyl halide.
The MD benzyl alcohol is 50 cents a gram in the 2003-2004 Alfa Aesar. It's from which it's made. may as well go to the bromide. To compare, the MD
phenylacetic acid is 6 bucks.
I don't like absolute ether. Better be out on a chicken ranch if you're messing with that. I wonder if THF is less of a bust. I was wondering
whether MIBE was better. They were trying to push it in some chemistry magazine. It's not. As they say, you'd have to go to some extreme vacuum to
get the solvent out. Those ethers stick in there forever. I don't know why. If you and SWIM are making something with ether, it always turns out to
be PCP.
I really think the world aspartame consortium is setting us up to replace all current amphetamine methods with one starting from phenylalanine. look
it up (Merck Index?). The optically active methamphetamine comes out by using the convenient other antipode not used to make aspartame. How much
aspartame do they make? Look at those modern reagents: complex hydride reducing agents and protecting groups.
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tupence_hapeny
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Here is a reduction of the phenylalaninal to phenylalaninol using only baker's yeast:
Here is the relevant section (experimental) of the article:
Quote: | 4.1. General procedure for bioreduction of α-substituted-cinnamaldehydes
Respective -substituted-cinnamaldehyde (4.7 mmol) dissolved d in 1.5 ml of ethanol was added to a mixture of 25 g dry baker’s yeast (Emulzint®)
and 10.4 g of glucose in 250 ml of water at 30 ◦C and pH = 5.5 (the pH of the fermenting yeast mixture was adjusted to 5.5 by the addition of
saturated sodium carbonate solution). The resulting suspension was stirred in an orbital shaker (200 rpm) at 30 ◦C until full conversion (48 h).
The product was extracted with CH2Cl2 and purified by column chromatography using hexane/ethyl acetate (7:3).
4.2. 2-Azido-3-phenyl-2-propenal (5)
To a stirred slurry of 1.2 g (18.5 mmol) of sodium azide in 20 ml of acetonitrile cooled methanol-dry ice bath, 3.0 g (18.5 mmol) of iodine
monochloride in 10 ml of acetonitrile was slowly added over a period of 10 min. The reaction mixture was stirred for an additional 10 min. followed by
addition of 2.3 g (18.2 mmol) of the cinnamaldehyde, and then allowed to warm to room temperature and stirred for 6 h.
The red-brown slurry was poured into 100 ml of water, the adduct was extracted with 200 ml of ether and washed with 300 ml of 5% sodium thiosulfate
aqueous solution in three portions leaving a colourless solution. The organic phase was dried on MgSO4. Evaporation of the solvent furnished crude
azide adduct (slightly orange) and used in the preparation of 5.
A solution of 5.0 g (16.6 mmol) of azide adduct (3-azido-2-iodo-3-phenylpropanal) and 4.0 g (61.5 mmol) of sodium azide in 30 ml of DMF (dried over
molecular sieves, type 4A) was stirred for 1 h at room temperature. The solution was then poured into a mixture of water–ether, and the ether layer
was washed with water and dried (MgSO4). Evaporation of the solvent furnished crude aldehyde 5.
Purification was achieved by flash column chromatography using hexane/ethyl acetate (7:3), affording 5, a yellow crystalline solid, mp 73–74
◦C, 96% yield...
4.3. (S)-2-Azido-3-phenyl-1-propanol ((S)-6)
When 0.8 g (4.7 mmol) of 2-azido-3-phenylpropenal 5 was subjected to the general procedure for bioreduction, the isolated product was (S)-6 (0.8 g,
97.7%) as a yellow oil...
4.4. 2-Bromo-3-phenyl-2-propenal (7)
A solution of 5.0 g (37.88 mmol) of cinnamaldehyde in 15 ml of CCl4 was cooled to 0 ◦C and treated dropwise with 6.1 g (38.1 mmol) of bromine in
5ml of CCl4. The mixture was stirred vigorously during 1 h, washed with a aqueous solution of sodium bisulfite and the organic phase was dried on
MgSO4. Evaporation of the solvent furnished crude aldehyde 7.
Purification was achieved by flash column chromatography using hexane/ethyl acetate (7:3), affording 7, a yellow crystalline solid, mp 72 ◦C,
87.6% yield...
4.5. (S)-2-Bromo-3-phenyl-1-propanol (S)-8
When 1.0 g (4.7 mmol) of 2-bromo-3-phenyl-2-propenal 7 was subjected to the general procedure for bioreduction, the isolated product was (S)-8 (1.0 g,
98.1%) as a yellow oil... |
I have as yet been unable to upload the article, so the details above are provided in an abridged format (without the calculated/found's).
The article itself is:
L.C. Fardelone et al, 'Baker’s yeast mediated asymmetric reduction of cinnamaldehyde derivatives' Journal of Molecular Catalysis B: Enzymatic 29
(2004) 41–45
The direct bromination of cinnamaldehyde and subsequent bio-reduction of the same offers some promise - however, what caught my eye is the idea that a
protected (benzyl/phthaloyl/etc) phenylalanine (or variant upon the same theme) could be reduced via yeast to the alcohol. Deprotection via reduction
(would HI work with Benzyl?) which may also affect reduction of the amino alcohol to amphetamine.
Thoughts would be good...
BTW, what methods could be used to reduce amino esters to amino aldehydes apart from the sodium amalgam?
[Edited on 16-5-2007 by tupence_hapeny]
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roamingnome
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theoretical considerations only
i wonder what the point sometimes is
i see time and time again discovery and backtracking
like enlightenment and dark age...
but who am i ?
http://www.rsc.org/delivery/_ArticleLinking/DisplayArticleFo...
http://cat.inist.fr/?aModele=afficheN&cpsidt=14930434
no nitro no bromine no problem
http://www.rsc.org/ej/CP/2004/b404889j/b404889j-u1.gif
uh boss?
yes igor
what should I do with the gif#1 uh....
well igor why dont you exspose it with a stiochometric excess of benzene possibly with micro orfice injectors
wow boss but how do it purify it?
well the resulting condensate which would be benzene water enriched with a syntheon known as p2p
could be driped into a bisulphite solution
then what?
now now igor... lets not get carried away
[Edited on 15-5-2007 by roamingnome]
[Edited on 15-5-2007 by roamingnome]
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solo
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Reference Information
Reaction of Hydroxyl Radical with Acetone. 2. Products and Reaction Mechanism
Ranajit K. Talukdar, Tomasz Gierczak, † David C. McCabe,‡ and A. R. Ravishankara
J. Phys. Chem. A 2003, 107, 5021-5032
Abstract
The products of the reaction of OH with acetone (OH + CH3C(O)CH3 f products) were investigated using a discharge flow tube coupled to a chemical
ionization mass spectrometer. It was shown that the yield of acetic acid from the reaction was less than 1% between 237 and 353 K. The yield of
acetonyl radical was measured to be (96 ( 11)%, independent of temperature, between 242 and 350 K. The rate coefficients for the reaction were
measured with this system to be the same as those reported in part 1 (J. Phys. Chem. A 2003, 107, 5014). The rate coefficients for the removal of OH
(V)1) by acetone and acetone-d6 were shown to be (2.67 ( 0.15) × 1011 and (3.45 ( 0.24) × 10-11 cm3 molecule-1 s-1, respectively, at 295 K. It was
shown that the enthalpy of reaction for the formation of an OH-acetone adduct is more than -8 kcal mol1 (i.e., the adduct is bound by at most 8 kcal
mol-1) at 203 K. On the basis of these observations and those from part 1, we deduce that the reaction of OH with acetone occurs through a
hydrogen-bonded complex that gives almost exclusively CH3C(O)CH2 and H2O. The atmospheric implications of our findings are discussed. 5021J. Phys.
Chem. A 2003, 107, 5021-5032
[Edited on 16-5-2007 by solo]
Attachment: Reaction of Hydroxyl Radical with Acetone. 2. Products and Reaction Mechanism.pdf (186kB) This file has been downloaded 1987 times
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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solo
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Quote: | Originally posted by tupence_hapeny
Here is a reduction of the phenylalaninal to phenylalaninol using only baker's yeast:
Here is the relevant section (experimental) of the article:
Quote: | 4.1. General procedure for bioreduction of α-substituted-cinnamaldehydes
Respective -substituted-cinnamaldehyde (4.7 mmol) dissolved d in 1.5 ml of ethanol was added to a mixture of 25 g dry baker’s yeast (Emulzint®)
and 10.4 g of glucose in 250 ml of water at 30 ◦C and pH = 5.5 (the pH of the fermenting yeast mixture was adjusted to 5.5 by the addition of
saturated sodium carbonate solution). The resulting suspension was stirred in an orbital shaker (200 rpm) at 30 ◦C until full conversion (48 h).
The product was extracted with CH2Cl2 and purified by column chromatography using hexane/ethyl acetate (7:3).
4.2. 2-Azido-3-phenyl-2-propenal (5)
To a stirred slurry of 1.2 g (18.5 mmol) of sodium azide in 20 ml of acetonitrile cooled methanol-dry ice bath, 3.0 g (18.5 mmol) of iodine
monochloride in 10 ml of acetonitrile was slowly added over a period of 10 min. The reaction mixture was stirred for an additional 10 min. followed by
addition of 2.3 g (18.2 mmol) of the cinnamaldehyde, and then allowed to warm to room temperature and stirred for 6 h.
The red-brown slurry was poured into 100 ml of water, the adduct was extracted with 200 ml of ether and washed with 300 ml of 5% sodium thiosulfate
aqueous solution in three portions leaving a colourless solution. The organic phase was dried on MgSO4. Evaporation of the solvent furnished crude
azide adduct (slightly orange) and used in the preparation of 5.
A solution of 5.0 g (16.6 mmol) of azide adduct (3-azido-2-iodo-3-phenylpropanal) and 4.0 g (61.5 mmol) of sodium azide in 30 ml of DMF (dried over
molecular sieves, type 4A) was stirred for 1 h at room temperature. The solution was then poured into a mixture of water–ether, and the ether layer
was washed with water and dried (MgSO4). Evaporation of the solvent furnished crude aldehyde 5.
Purification was achieved by flash column chromatography using hexane/ethyl acetate (7:3), affording 5, a yellow crystalline solid, mp 73–74
◦C, 96% yield...
4.3. (S)-2-Azido-3-phenyl-1-propanol ((S)-6)
When 0.8 g (4.7 mmol) of 2-azido-3-phenylpropenal 5 was subjected to the general procedure for bioreduction, the isolated product was (S)-6 (0.8 g,
97.7%) as a yellow oil...
4.4. 2-Bromo-3-phenyl-2-propenal (7)
A solution of 5.0 g (37.88 mmol) of cinnamaldehyde in 15 ml of CCl4 was cooled to 0 ◦C and treated dropwise with 6.1 g (38.1 mmol) of bromine in
5ml of CCl4. The mixture was stirred vigorously during 1 h, washed with a aqueous solution of sodium bisulfite and the organic phase was dried on
MgSO4. Evaporation of the solvent furnished crude aldehyde 7.
Purification was achieved by flash column chromatography using hexane/ethyl acetate (7:3), affording 7, a yellow crystalline solid, mp 72 ◦C,
87.6% yield...
4.5. (S)-2-Bromo-3-phenyl-1-propanol (S)-8
When 1.0 g (4.7 mmol) of 2-bromo-3-phenyl-2-propenal 7 was subjected to the general procedure for bioreduction, the isolated product was (S)-8 (1.0 g,
98.1%) as a yellow oil... |
I have as yet been unable to upload the article, so the details above are provided in an abridged format (without the calculated/found's).
The article itself is:
L.C. Fardelone et al, 'Baker’s yeast mediated asymmetric reduction of cinnamaldehyde derivatives' Journal of Molecular Catalysis B: Enzymatic 29
(2004) 41–45
The direct bromination of cinnamaldehyde and subsequent bio-reduction of the same offers some promise - however, what caught my eye is the idea that a
protected (benzyl/phthaloyl/etc) phenylalanine (or variant upon the same theme) could be reduced via yeast to the alcohol. Deprotection via reduction
(would HI work with Benzyl?) which may also affect reduction of the amino alcohol to amphetamine.
Thoughts would be good...
BTW, what methods could be used to reduce amino esters to amino aldehydes apart from the sodium amalgam?
[Edited on 16-5-2007 by tupence_hapeny] |
Reference Information
Baker’s yeast mediated asymmetric reduction of cinnamaldehyde derivatives
L.C. Fardelone et al, '
Journal of Molecular Catalysis B: Enzymatic 29 (2004) 41–45
Abstract
The enantioselective reduction of cinnamaldehyde derivatives is an attractive strategy to prepare various optically active multifunctional
molecules that can be used as chiral building blocks for the synthesis of some HIV-protease inhibitors. The asymmetric reduction
with pH adjusted to 5.5 of -substituted-cinnamaldehydes (Br, N3) mediated by baker’s yeast (Saccharomyces cerevisiae) yielded
-substituted-3-phenyl-1-propanol in excellent enantiomeric excesses and yields.
Keywords HIV-protease inhibitors; Baker’s yeast; -Substituted-3-phenyl-1-propanol
Attachment: Baker’s yeast mediated asymmetric reduction of cinnamaldehyde derivatives.pdf (102kB) This file has been downloaded 2662 times
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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tupence_hapeny
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Here is a possible quaternary amine approach to reduction, which I suggest simply because I have seen that the only direct (non-LAH) reduction of
phenylalanine to phenylalaninol is via a neo-birch style (Akabori) reduction with Na/Hg. This agent is an electrolytically generated quat
(tetra-butylammonium (TBAOH)) amalgam.
It reduces methoxybenzenes similarly (both in activity & yield) to a birch reduction according to that article (and also this one). The setup
appears to be relatively simple for an electrolytic process, a mercury pool cathode & a stainless-steel anode in an undivided cell.
However, I re-emphasise that I have no way of knowing if this reaction works.... Although it has recently been used to remove acyl derivatives in this
article.
In addition to which, after a degree of searching, I have found two mentions (only) of the Ra-Ni reduction of phenylalanine to phenylalaninol, the first of which merely mentions the second which is more detailed. The absence of further reference may be due to problems with the reaction, or may signal the widespread use of LAH
for such reductions instead.
Finally, the reduction of the phenylalaninal to phenylalaninol is also able to be achieved in a number of ways, one of which is that provided by Solo
(on my behalf, above), whilst more information on the yeast reduction of aldehydes & ketones is available - the best reduction is probably this one, using Ni-Zr with 2-propanol (isopropanol).
tup
[Edited on 20-5-2007 by tupence_hapeny]
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Nicodem
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Quote: | Originally posted by Nicodem
If you have a reference to support your claim I would like to see it (even though it would be the most idiotic synthesis of nitroethane ever, but who
cares about something as cheap as nitroethane anyways). |
Since the one to whom this was directed never replied, I will reply to myself and provide the referenced paper in the attachment. The trick seems to
be to work at -90°C in THF/HMPT. Though this C-alkylation of doubly deprotonated nitroalkanes was checked only with two alkyl halides (1-bromopentane
and 1-iodohexane) and is anything but practical it is nevertheless an interesting curiosity.
alpha, alpha-Doubly Deprotonated Nitroalkanes. Enhancement of the C-Nucleophilicity of Nitronates.
Dieter Seebach and Friedrich Lehr
Angew. Chem. lnt. Ed. Engl., 15 (1976) 505-506.
Attachment: Doubly Deprotonated Nitroalkanes_Enhancement of the C-Nucleophilicity of Nitronates.pdf (205kB) This file has been downloaded 1454 times
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Read the The ScienceMadness Guidelines!
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einstein(not)
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Quote: | Originally posted by solo
Quote: | Originally posted by Organikum
The direct reductionof phenylalanine to amphetamine is done with triethylsilane in trifluoroacetic acid IIRC. The silane being meanwhile a common
reagent AFAIK.
Reductions with this sytem almost always result in practically quantitative yields, thus beating the holy shit out of LiAlH. |
----------------------------------------------------------------------------------------
Selectivities in Ionic Reductions of Alcohols and Ketones with Triethyisilane / Trifluoroacetic Acid
Herbert Mayr and Barbara Dogan
Tetrahedron Letters, Vol. 38, No. 6, pp. 1013-1016, 1997
Abstract The relative rates of reduction of alcohols and ketones by Et3SiH/CF3CO2H have been de- termined by competition experiments
in order to derive scope and seleetivities of these reactions.
[Edited on 7-1-2007 by solo] |
This only speaks to alcohols and ketones. What am I missing?
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Ritter
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Quote: | Originally posted by Furch
Ph-CHO + CH3NO2 --Base--> Ph-CH=CH-NO2
This condensation I don't even need to explain, as it's such a well known reaction in these circuits.
Ph-CH=CH-NO2 --NaBH4--> Ph-CH2-CH2-NO2
Lots of sources for this kind of reduction as well...
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Anytime you can avoid potentially unwanted scrutiny (as well as expense) is a good thing. Why bother with borohydride when you can use yeast?
From US Patent Application Publication US2005/0084943:
http://tinyurl.com/4eu38h
Quote: | Preparation of 2-nitro-3-phenylpropane
(Z)-2-nitro-3-phenyl-2-propene (151 mg, 1 mmol) was reacted with yeast (5 g) and water (5 ml) according to Method 1. The product was isolated
as a racemic mixture of products in 41% yield. Reaction according to Method II also resulted in a racemic mixture of products in 38% yield.
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Ritter
Ritter
=============================
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Klute
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A: bad yields
B: messy workup
C:Huge amount of yest
D:unpredictable results
E:NaBH4 doesn't bring scrutiny
IMHO
Whene xtracting that fermented mess, you will surely spend more in solvents that you would haev spent in NaBH4.. And if you recycle your solvents,
you will loose time redistg them..
The NaBH4 reduction of the double bond of nitroalkenes is backe dup with alot of info, and lots of first-hand practical results. I've never heard of
anyone using yeast with succes besides patents.
[Edited on 20-6-2008 by Klute]
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Ritter
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Quote: | Originally posted by Klute
A: bad yields
B: messy workup
C:Huge amount of yest
D:unpredictable results
E:NaBH4 doesn't bring scrutiny
IMHO
Whene xtracting that fermented mess, you will surely spend more in solvents that you would haev spent in NaBH4.. And if you recycle your solvents,
you will loose time redistg them..
The NaBH4 reduction of the double bond of nitroalkenes is backe dup with alot of info, and lots of first-hand practical results. I've never heard of
anyone using yeast with succes besides patents.
[Edited on 20-6-2008 by Klute] |
May be. I offered this reference only for information as I had come across it while working on something unrelated. If buying reagents like NaBH4
isn't a problem in France, then disregard.
Ritter
=============================
\"The production of too many useful things results in too many useless people.\"
Karl Marx
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woelen
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Thread Split 9-12-2014 at 06:58 |
CuReUS
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instead of reacting methyl iodide with 2- phenylnitroethane ,could simmons smith reaction be done on beta nitrostyrene followed by reduction
http://en.wikipedia.org/wiki/Simmons%E2%80%93Smith_reaction
during reduction,the cyclopropane ring breaks and the nitro group gets reduced to amine to give amphetamine.
i am only interested in the chemistry involved, as the reaction cannot be done now as nitromethane is also watched and the simmons smith reaction
needs diiodomethane,which is not OTC
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chemrox
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@ Solo - could you repost the ref on page 1 or convert and post it? even better! The method is so well known it was used by Shulgin and many others
for substituted PEAs and amphetamines. nitromethane -> pea nitroethane - amphetamine.. ad nauseum. I believe this method was even published by
"Strike" and "Uncle Fester.." I find this an interesting subject especially with respect to regioselective methods. Either r or s amphetamine is a
good base for separating chiral acids. We used to have l-amphetamine on the shelves in our graduate labs. They seemed to go down a bit during final
weeks ;^)
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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