"Illicit" Ketamine Manufacture - What's the reality?

[Dioxy]

I posted a short question on a thread about ketamine earlier but I thought it might be worth starting a thread. I apologise if this is the wrong place for it.

It's come to my attention through the usual insubstantiated routes that Ketamine is being made illegally in some countries. I was always under the impression that the vast majority of it came from legitimate suppliers with regulated manufacturing processes.

After the 2010 Ketamine drought of the UK, it slightly concerns me that, if illicit production starts to happen in clandestine labs with no regulation, we could face similar issues that we do with, for example, MDMA manufacture, where the process is quite often imperfect and leaves potentially (more) toxic residual chemicals.

Is this information correct? And if so, what kind of impurities can we expect to see from amateur synthesis? What do we know about the toxicity of these chemicals?

These are the questions I pose to you, the legion of Bluelight

 

[ebola?]

I could be wrong, but I'd imagine illicit 'ketamine' (varied substituted pcp analogues) to become more common, as the synthetic routes are easier.

ebola

 

[Dioxy]

Is there any possible way to distinguish between ketamine and other arylcyclohexylamines with a consumer chemical test? I presume mandelin would test the same for both.

I would personally like to avoid using any other PCP derivative.

 

[seep]

Someone could TLC some USP ketamine and publish the procedure & results. They'd have to figure out the mobile phase. The pharmacopoeia recommends 35% MeOH to 65% buffer (the buffer being 6 mL TEA and 5.75g ammonium phosphate dissolved in a liter of water and adjusted to a pH of 3.0 with phosphoric acid).

 

[MurphyClox]

Petyunin, G. P.; Guzenko, N. V.
"Determination of ketamine by thin-layer chromatography."
Visnik Farmatsii 2007, (3), pp.21-23

Abstract
The optimal analytical conditions for ketamine determination by TLC were examined using 14 mobile phases. Ketamine was analyzed simultaneously with its structural analogs phencyclidine and tramadol and phenylalkylamine derivatives. They included mixtures of urinary metabolites of metamphetamine and tramadol, ephedrone, ephedrine, pseudoephedrine, amphetamine, metamphetamine, 3,4-methylenedioxyamphetamine, 2,5-dimethoxyamphetamine, dextropropoxyphene, dextromethorphan, phenylephrine, and phenylpropanolamine.
The detection reagents included Dragendorff solution, 1% ninhydrin in conc. H2SO4, 1% ninhydrin in acetone, ammoniacal solution of silver nitrate, and successive spraying with 1% ninhydrine in acetone followed by the Marki solution.
The best analytical selectivity was obtained with the mobile phases of hexane-acetone (2:1).
The best TLC spot visualization was achieved with 1% ninhydrine solution in acetone and ammoniacal solution of silver nitrate, and successive spraying with 1% ninhydrine in acetone followed by the Marki solution.

No idea about Rf-values though..


When impregnating the TLC-foil with (-)-mandelic acid, one can even separate ketamine's enantiomers. Alternatively, (+)-tartaric acid can be used as chiral mobile phase auxiliary reagent, like in the mixture MeCN/MeOH//(+)-tartaric acid (0.5% in water, pH 5)/AcOH (7 : 1 : 1.1 : 0.7; v/v). See Chromatographia 2008, 68, p.1045 for further details.


Further variation of the solvent system is of course possible. Some examples:
a) EtOAc/MeOH/30% NH3 (85 : 10 : 19)
b) Cyclohexane/Toluene/EtNH (65 : 25: 10)
c) EtOAc/CHCl3 (50 : 50)
d) Acetone (plate dipped in 0.1 M KOH-solution before)
Using HPTLC-plates, the Rf-values for ketamine are 0.83, 0.41, 0.24 and 0.76 (a to d). HPTLC-plates are a bit unusual for the hobby-chemist, but the values provide a good guideline for what can be expected with normal GF254 silica plates. (Ref: Journal of chromatography A 1985, 350(1), p.151)


PEACE! - Murphy

 

[vecktor]

Someone could TLC some USP ketamine and publish the procedure & results. They'd have to figure out the mobile phase. The pharmacopoeia recommends 35% MeOH to 65% buffer (the buffer being 6 mL TEA and 5.75g ammonium phosphate dissolved in a liter of water and adjusted to a pH of 3.0 with phosphoric acid).

that mobile phase is for reverse phase chromatography probably HPLC and isn't going to do a lot of good unless you have RP TLC plates