ephedrine CTH with Perchloric Acid to desoxyephedrine?

joe_aldehyde · huxleys associate

does anybody (except my professional cunt) have reference apart from what i can find here or at the hive (very little, tho) regarding the catalytic hydrogenation of ephedrine to methedrine using perchloric acid, 10% Pd/C at atmospheric pressure?

lurker4711 · Sun May 29, 2005 7:37 pm

Rosenmund has reduced ephedrine with preloaded Pd/BaSO4 (10%) and perchloric acid (70%) as activator. I can´t see why this shouldn´t work as CTH with modern Pd/C catalysts.

After my best of knowledge this reaction depends strongly on the quality of the catalyst - high quality catalysts as from DEGUSSA will work - many other won´t.

joe_aldehyde · huxleys associate

oh, perfect - i have 100g degussa 10% Pd/C and a fresh bottle of HClO4.

i have the description of his reduction, but i don't get where the hydrogen comes from. did he do it in a pipe bomb under pressure or just atmospheric pressure?
i'd be glad if anybody could come up with the experimental procedure he used.

java · Consumer

You need to hydrogenate with the method described, such as with a Parr Hydrogenator....or a home made version, of course one can load a vessel with the Hydrogen that will hold 3 bar and approach it that way ...................there is a full write up in the Hive files....search.....java

lurker4711 · Mon May 30, 2005 3:28 am

Rosenmund used a very high ratio of substrate to catalyst - 2/1 w/w and preloaded the catalyst with hydrogen before use. No pressure, no external or internal hydrogen source except the preloaded catalyst.

I suppose that a internal CTH hydrogen source would make it possibe to use much less catalyst. Some pressure wouldn´t hurt - 3 bar should suffice nicely. Temp was 80°C IIRC and time 4 hours.

But I would have to look this up to be sure.

joe_aldehyde · huxleys associate

i don't know if i can manage to use pressure in any form, i only have experience with ordinary glass vessels. i have seen some very thick walled Al pipes somewhere that would make a nice bomb, but then again, Al dissolves in acid Sad

can i pressurize ordinary glassware as well? it's all DURAN i have.
don't know where i'd get hydrogen gas anyways, would have to make it from M(s) + H+ and that's not gonna build up big pressure, right?

java · Consumer

There is a particular need to weld aluminum and other metals where both argon and Hydrogen are employed usually found at the weld shop ...........as I said search the Hive files where WixardX talks about the procedure with ratios.......java

joe_aldehyde · huxleys associate

sorry java i have previously searched the hive files for "perchloric", thats all i could think of. nothing found! Sad

loki · guinea pig

getting the interior of a metal container coated with teflon can be done too, and is perfectly effective for just about anything that doesn't require a temperature above about 250. I'm not sure what the procedure is for producing this coating tho.

heavywall glassware that is rated to be able to take pressure below about 1/6th of an atmosphere (about 36 torr) probably will be more than capable of withstanding 3 atmospheres. of course test it, but pressure and vacuum produce much the same stresses on glass, although the geometry of the flasks may not have as much strength on outward pressure versus inward pressure (specifically at the point where the neck emerges). I believe there is heavywall pyrex with a special plastic coating that would probably suit this task, and be safer too. I think, at 3 atm, a parr hydrogenator is a bit of overkill.

If the temperature permits, something like a champagne bottle could be used, but this would be useless above about 50 degrees. At 80 degrees, thick polypropylene would probably be ok to use, but probably only as a one-shot... i'm not certain about compatibilities of polyethylene and percarboxylic acids tho, at a guess i'd say it's ok, being that this is the plastic it is often packaged in, but at 80 degrees a suddenly exothermic reaction would probably turn into an explosion, and possibly a fireball if one was unlucky. A bit of investigation into plastics may be worthwhile. Also, I have seen fairly heavy grade teflon flasks before in catalogues (i think it was just beakers and earlenmeyers).

joe_aldehyde · huxleys associate

nothing useful found using your keywords, i_a.

loki, why doesn't a champagne bottle stand more than 50 deg.c?

java · Consumer

If you try your search by the name reaction "ephedrine ester catalytic reduction", you will get some results such as the following..........

Excerp

Synthetic Reductions in Clandestine Amphetamine and methedrine Laboratories: A Review

by Andrew Allen and Thomas S. Cantrell, Forensic Science International, Vol. 42, 183-199 (1989)
HTML and graphics by Rhodium
with help from PrimoPyro

Summary

A review of synthetic reductions utilized in the clandestine manufacture of amphetamine and methedrine is presented. General discussions on the mechanism of heterogenous catalysis, dissolving metals, hydrides and non-metal reductions used in the manufacture of amphetamine and methedrine with over 90 references are presented.

Introduction
This review addresses reductions in clandestine methedrine and amphetamine synthesis. Central to the diverse routes published for the synthesis of amphetamine and methedrine is a reductive step at some point in the synthesis. Of 95 references surveyed concerning the synthesis of these controlled drugs, all but ten utilize a reductive approach. Since such diversity exists in these approahes, we felt that a composite literature review and discussion of the chemistry involved would help forensic chemists charged with investigating these clandestine laboratories. Secondly, we felt that a composite reference list would be of assistance in correlating notes or procedures found in clandestine laboratory sites to the open literature. Finally, two literature review articles in the forensic area have appeared and both were devoid of extensive references [1,2].

An overview of synthetic approaches to methedrine and amphetamine utilized reductive routes is outlined in tables 1 and 2. Table 1 is organized by the type of catalytic surface or reductive species; i.e. Pd, Pt, LiAlH4, HCOOH etc. Table 2 is organized by the synthetic route or intermediate; i.e. Leuckart, Schiff base, oxime, nitrostyrene, etc. Figures 1-12 illustrate the chemical formulas of the chemical reduction routes to amphetamine and methedrine. References [3,72] are annotated with the type of reductive catalyst/reagent and route utilized. Chemical Abstracts citations [C.A. Vol, Page (year)] are included for each reference for ease of cross reference with cryptic notes often found in clandestine laboratory sites. Finally, the recurrent use of the terminology "open literature" refers to legitimate, accredited journals as opposed to underground publications or notes passed between clandestine manufacturers.

...........as quoted from,
https://www.synthetikal.com/Rhodiums_pdfs/chemistry/amphetamine.reduction.html

joe_aldehyde · huxleys associate

i have found that one java BUT well...you see, it's not referencing the experimental section. that's what i'm looking for - all the sources i found are lacking the exact description of what had been done. it just seems like i have to work it out for myself Smile

btw i just got 10 grams of Pt/Pd on Al2O3...isn't it supposed to be much more effective than Pd/C alone? i wonder what we can do to our nasty little ephedrine with that catalyst.

loki · guinea pig

a champagne bottle probably will survive the reaction, but at 80 degrees, a moderate shock could result in it breaking, as could a sufficiently cold object touching it, especially pressurised, as standard soda glass becomes very brittle at around this temperature (i learned this the hard way bringing a bottle of just finished reducing volume plant material aqueous extract that was still hot, i bumped it on the side of a step and it fell apart.

joe_aldehyde · huxleys associate

ok...i see. i'm not really comfortable with pressure :/
since i cannot generate greater pressure than what comes from a dissolving metal H2 source, this doesn't apply to my capabilities anyways.

maybe i will waste my brand-new Pt/Pd on Al2O3 on this. should also be a nice one for CTH, yes? if i leave out the substrate in a CTH, would this be suitable to load my catalyst with H2?

lurker4711 · Tue May 31, 2005 2:07 am

Actually with a CTH type reaction and preloaded catalyst you should need almost no pressure - nothing a RBF couldn´t stand. Fix a metal-net around the bottle and you are safe.

The catalyst is put into GAA and hydrohgen is vented through for some hours. Preloaded. You shouldn´t use dissolving metal in situ and when you use for example Al/HCl for the generation you should wash the gas by bubbling it through dil. KMnO4/H2O for cleaning or you *will* poison your catalyst.