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Monosodium Glutamate

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Acyl: Yeah it turns out I was looking at the first incarnation of the thread, not the one you just linked me to. Looking better now. That final aldehyde will be able to be hydrogenated nicely with some Urushibara nickel or cobalt, I expect. (or a mild hydride, if that's more your style, but they're more suspect to get than some nickel chloride)
Cool, a truly OTC route :) .
 
So, I'm guessing this would result in the sodium salt or no? This is sweet. They thought clandestine manufacture of meth from sudafed and water purifier was bad.... Now they need to deal with NaGHB from MSG and pool cleaner hahahahahahaha
 
^ Well, garage-chemist says the Sandmeyer reaction of HNO2 + R-NH2 makes a big mess. But the same reaction used in making that 4-COOH-GBL seems to produce good yields. I'm not sure what to think.
Evebn if GABA isn't OTC (like where I live, NZ, where it's listed as a GHB analog =/) you can make it from the TCCA oxidation of glutamic acid (get from MSG) to the nitrile (~90% yield), and then easily reduce that the the amine (GABA).
 
The exact reaction has been tested and documented on orgsyn.org . The reference I pointed you too has all the info you need.. it makes no difference what the other guy said about generalized reactions with amines and nitrites, you do it properly and follow that method you should observe similar results.
 
Nah I mean going from GABA to GBL in one step. If it works with GABA, I say the synthesis I thought of is a very viable alternative.

Two routes with similar accessibility to the same target :) .

The one you've been discussing: glutamic acid -> 4-COOH-GBL -> 4-carboxy-butanal - > GHB.
The one i'm now suggesting: glutamic acid -> 4-carboxy-butylnitrile -> GABA -> GBL (-> GHB).

The only reason I don't like the one you've been suggesting is the final reaction, the reduction of aldehyde to alcohol, which uses suspicious reagents, whereas mine can be done without these. (the reduction of nitrile to amine is easy, and done with Urishubara catalysts and 1atm H2.) (Not that i'd ever carry it out of course, the theory is just interesting :))
 
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^ why would one bother going from MSG/glutamic acid to GHB if GABA is an intermediate?
I don't know which is cheaper in bulk but I know GABA is easily obtainable so why not just use the direct route? Is MSG that much easier to get/cheaper? Or is this just for novelty (synthesis masturbation)?
 
GABA is not OTC everywhere (like where I live, where it's classed as a GHB analog, despite it being a basic neurotransmitter and building block of life, *sigh*).
If you CAN get it OTC, then woohoo, you save lots of time and effort (in imaginaryland, where imaginary syntheses take place).
But mostly this is chemical masturbation, yes :p . Fun for the whole family!
 
GABA is considered a GHB analogue? Wow, that's really weird, since it has no psychoactive effect.

I wonder if that was more an attempt to keep a precursor out of the hands of would be chemists.
 
MattPsy said:
^ Well, garage-chemist says the Sandmeyer reaction of HNO2 + R-NH2 makes a big mess. But the same reaction used in making that 4-COOH-GBL seems to produce good yields. I'm not sure what to think.
Evebn if GABA isn't OTC (like where I live, NZ, where it's listed as a GHB analog =/) you can make it from the TCCA oxidation of glutamic acid (get from MSG) to the nitrile (~90% yield), and then easily reduce that the the amine (GABA).
Click to expand...

I'm not a "garage-chemist".

In general reaction of aliphatic amines under Sandmeyer conditions typically does give a difficult mix of products including the target alcohol, alkenes, and other side reaction products depnding on the conditions.

In this case it would appear to work. Presumably the cyclization to the lactone is favored enough to prevent most side reactions. In which acse I would probably guess that GABA under Sandmeyer conditions probably also gives the desired end product without additional synthetic steps.
 
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Yes, Id imagine its more favourable due to the alpha carboxylic acid. It seems to stabilize the intermediate before the actual cyclization.

I doubt the same would happen with GABA.
 
GABA is considered a GHB analogue? Wow, that's really weird, since it has no psychoactive effect.

I wonder if that was more an attempt to keep a precursor out of the hands of would be chemists.
Click to expand...

Huh?
 
retired_chemist: Sorry, no disrespect intended at all, wrote it down after having just been browsing Sciencemadness, I think I may have seen the name "garage chemist" there and it was transposed. :)

Yeah GABA is considered a GHB analog where I live... I guess because it's a precursor. Pretty silly though, with all the different ways it can be made. And the fact it's a natural amino acid present in pretty much everything organic.
 
Btw, to answer the MSG question, MSG can be bought at about $1 for numerous grams. So, how complex would this be in the end?
 
I've just looked at the reaction. The shroomery jpg contains a different mechanism for the reaction than the one listed on Organic Syntheses. I'm skeptical but not completely dismissive about the proposed mechanism in the Organic Syntheses article, but the transition state mechanism on the shroomery jpeg doesn't make any sense. Under conditions of strong base both acids would be deprotonated. I tried to explain all of the flaws in this mechanism, but unless there are about five steps I'm not seeing, it doesn't make any sense. The biggest problem seems to be the violation of the carbonyl carbon octet.
 
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