well the title says it all can cathinone be used instead of oxidizing ephedrine?

Cathinone is to methcatinone as amphetamine is to methamphetamine. What your asking has nothing to do with oxidizing anything, you'd have to add a methyl group to the cathinone which isn't really at all practical. To be honest I'm a little confused by your question. It'd make way more sense to just oxidize the ephedrine with dichromate [sure dichromates are scary as shit, but the KMnO4 synth simply doesn't work, there seems to be a lot of miss information floating around about that one, if only it was so easy!].

sorry. yes i kno what it is comparable i was asking if it was easyier to go from cathinone to m-cat, or if it was easyer to oxidize ephedrine. and obviously i had read some misinfo on the ephedrine to m=cat process.

what would be the process to go from ephedrine to m=cat then?

I don't see why a reductive amination with formaldehyde / formalin shouldn't work to give the methylated product...

Reductive amination is going to be messy because of the ketone on the catinone. It'll react with itself and cause all sorts of side rxns. Anyhow to go from ephedrine to m-cat see: http://www.erowid.org/archive/rhodium/chemistry/catsynth.jones.html

Be real careful with that however, dichromate salts will fuck you up.

Reductive amination is going to be messy because of the ketone on the catinone. It'll react with itself and cause all sorts of side rxns.

Duh!

That's an excellent point, and firm validation of the premise that one should think before posting...

:D


Though there's at least a sporting chance that one could control the extent of intramolecular reaction by careful choice of reaction conditions...


moving on... Is the permanganate route really that problematic? I thought most of the issues came from incorrect calculation of stoichiometry - i.e. people forget that KMnO4 will (theoretically) oxidise five equivalents of a substrate...

Are you guys fucking kidding me?

http://docs.google.com/Doc?id=ddwd3tqm_22gmpgr8fw

It doesn't get much easier than secondary alcohol oxidation.

EDIT: Fuck, I mean you don't even need solvents! :mad:

KMnO4 is always going to cause problems, it's waaaay to strong of an oxidizer even if you get the ratio just right and keep it cold you're pretty much guaranteed to over oxidize. I don't know how the idea of using KMnO4 became so wide spread but so far as I know it doesn't work at all.

I've never heard of 'Green oxidation's' before but it looks interesting, do you have any more information?

Another plausible solution to avoid using dichromate salts might be:
http://en.wikipedia.org/wiki/Oppenauer_oxidation

The reason I keep mentioning dichromate is that I know for sure they'll work, anything else and it's hearsay.

I've never heard of 'Green oxidation's' before but it looks interesting, do you have any more information?
Look up the articles. I can send most of the PDFs of the full articles your way if necessary.

Another plausible solution to avoid using dichromate salts might be:
http://en.wikipedia.org/wiki/Oppenauer_oxidation
Or bleach in nickel (II). Or carbonate in iodide/iodine. Or iron nitrate with a heteropoly acid catalyst. If you're seriously considering organnometal reagents for a simple oxidation you need to do some research.

The reason I keep mentioning dichromate is that I know for sure they'll work, anything else and it's hearsay.

If you consider ACS articles hearsay. :rolleyes:

You'll need a large excess of dichromate, unless you don't care if you have (pseudo)ephedrine in your mcat. Shit man, I gave you some of the easiest oxidation methods in the literature and you want to use the toxic, expensive, and environmentally-hazardous chromates? I never understood why meth cooks didn't just oxidize and pull a wolff-kishner on the ketone, but now I know that they probably googled "oxidation" and didn't like the first reaction on their screen. :rolleyes: Research your reactions for Christ's sake!

I'll check out the articles, thanks! What I mean by hearsay is that I don't know anything about those other reactions [without some more research obviously!] and I've never heard of anyone using them to oxidize ephedrine until now so I am not going to speculate as to if they'd be reasonable in this specific rxn or not. I do know that dichromate works for sure, and I wouldn't really suggest anyone use it - I totally agree with you it's nasty stuff, but it's all I'm sure of. I'd be really interested to know if anyone has actually successfully produced m-cat [at least mostly] OTC via one of those other reactions!

I'd also assume people make meth the way they do because of precursors and simplicities sake, there obviously isn't just one way to do it but for an example the old HI reduction with RP and I can be done all in one reaction vessel, no mess, everything OTC - It's almost impossible to screw it up. As soon as you start having to do multiple rxns with workups in between + using more 'exotic' [compared to traditional methods] chemicals the yield is going to go down and it's going to become less accessible to a lot of people.

Thanks for all the information I know I really appreciate it, and hopefully the OP does as well :P

I'll check out the articles, thanks! What I mean by hearsay is that I don't know anything about those other reactions [without some more research obviously!] and I've never heard of anyone using them to oxidize ephedrine until now
Well seeing as how most of those reactions were tested for tolerance to amines and aromatics, there's absolutely no reason for it not to work. Ephedrine is pretty cheap so there's really no reason not to experiment with a microscale batch. Mechanisms work the same way no matter what substrate you use (barring side reactions) so get to it!

so I am not going to speculate as to if they'd be reasonable in this specific rxn or not.
Maybe you should take an ochem course and realize that an oxidation is an oxidation is an oxidation. Berkeley has a good course online you should take a look at before you claim that all substances are unique to the same oxidation. The iodide/iodine oxidation works no matter what alcohol you use, it just absorbs protons. Do you think ANYBODY who has made MDMA ever hesitated to reductively aminate because he/she wondered if the same process would work on a substituted analogue? Fuck no. Chemistry ain't magic that's unique to each chemical; it's about scientifically determining the movement of electrons. All oxidations work the same way, and when they find a new alcohol, nobody will doubt that it will be oxidizable by the methods known in the literature (some of which I've included in my post). There is absolutely no reason to doubt that the methods outlined work identically to chromates, especially since chromate, nickel, and tungsten oxidations all use metal ester transition states.

I do know that dichromate works for sure, and I wouldn't really suggest anyone use it - I totally agree with you it's nasty stuff, but it's all I'm sure of. I'd be really interested to know if anyone has actually successfully produced m-cat [at least mostly] OTC via one of those other reactions!
It's irrelevant because oxidations proceed through the same mechanism each time. Get that into your head.

I'd also assume people make meth the way they do because of precursors and simplicities sake, there obviously isn't just one way to do it but for an example the old HI reduction with RP and I can be done all in one reaction vessel, no mess, everything OTC - It's almost impossible to screw it up. As soon as you start having to do multiple rxns with workups in between + using more 'exotic' [compared to traditional methods] chemicals the yield is going to go down and it's going to become less accessible to a lot of people.
It used to be that way. RP and HI are more difficult now than the old days, which is why I think hydrazine and oxidation would be easier now. The reaction can be one pot if one uses a bit of creativity.

Thanks for all the information I know I really appreciate it, and hopefully the OP does as well :P

You're welcome. But educate yourself on redox first. The mechanisms are identical every time (barring side reactions) so there's no reason to withhold judgment unless the reaction is totally novel and completely untested.

Oh don't get me wrong I'm not disagreeing with you at all, I understand that an oxidation is an oxidation etc. and if they've been tested with amines etc etc. I should work fine just as you said it would [I didn't know this, as I said, I don't know these reactions, you do! Until I read up on it I don't have an opinion besides your word - and you do seem to know what you're talking about, but I'm not going to make any sort of endorsement of an rxn to the OP when I know nothing about it]. All I was concerned with is that in some of these alternative reactions you might be making use of conditions or chemicals that have some sort of unintended effect when ephedrine is concerned. I realize that is very general but again I should re-illiterate I don't know anything about the processes you're suggesting, or what would specifically be involved. I'm not attacking you or saying you're wrong or holding judgment or anything. All I'm saying is I personally don't know if it will work or not, KMnO4 is something that I do know wont work and Dichromate is something I know will work.

When you say 'get to it!' I think you should be referring to the OP, I'm not interested in making m-cat I was just trying to help him out :P. So OP get to it and then report back!

WTF you're not OP? Skepticism is fine, but when the relevant functional groups have been tested, it's time to put doubt aside.

there's absolutely no reason for it not to work.


If you had any idea how many times I've done reactions that "have no reason not to work", only to have them fail horribly... you wouldn't make that assertion...!

If you had any idea how many times I've done reactions that "have no reason not to work", only to have them fail horribly... you wouldn't make that assertion...!

But surely they weren't as simple as oxidations with known mechanisms, right?

But surely they weren't as simple as oxidations with known mechanisms, right?


Oh yes, you'd be surprised...

You might also be surprised at the number of multistep total syntheses the fail at the [i]very]/i] last hurdle - final deprotection steps for example...

Tis a fickle fucker, that chemistry!