Hi everybody. I'm not a newbie at chemist, but not an Expert also.. So I'm asking for help from the Experts here to make a write up about the reduction of methcathinone to meth, getting rid of the carbonyl group by reducing it to methylene group by HI and hydrazine methods.
I have searched across the net and across BB Forum and is hard to find anything solid about it. There's a thread here in BB Forum mentioning about using Clemensen reduction to do this job, but without further details: (https://bbforum.org/en/threads/meth...-mercury-amalgam-and-hydrochloric-acid.16784/). I think Clemensen reduction will not work properly in this case cause it demands acidic environment that favor the formation of dimmers and sideproducts. Anybody here could present arguments that corroborate Clemensen Reduction works properly with amino ketones?
The literature presents some other methods to reduce carbonyl groups to methylene groups (Todd, D. (2011). The Wolff-Kishner Reduction. Organic Reactions, 378–422. doi 10.1002-0471264180.or004.08). Pd/C, and thioacetals with Raney Nickel are examples but rather unfeasible for me cause the complexity of the methods and the high cost of the raw material. So Wolff-Kishner Reduction presents a low cost, simple and efective method to reduce amino ketones without affect the amino group, since demands basic conditions. At other side, some articles say converting the ketone to a hydrazone, followed by treatment with a strong base at high temperatures, can induce rearrangements or deamination of the amino group. The question is: BOC protection of the amino group is or isn't mandatory in this case? Anybody here could present arguments that corroborate Wolff-Kishner Reduction works properly with amino ketones without amino group protection? Protect and desprotect tha amino group is a pain in the ass that would turn the process more expensive, tedious and time consuming.
The literature say HI, as a powerfull reducing agent can deoxigenate almost every substance at the right condictions. Is employed susscefully in the reduction of Ephedrine to meth, reducing the OH group to a methylene group. The methodology used is often using Red phosphorous and Iodine or H3PO2 and Iodine at reflux and temperatures between 100-160ºC. The role here is the formation of PI3 that act as a catalizer regenerating the HI from the Iodine formed from the cleavage of the OH radical into a methylene group and the H3PO2 from the H3PO3 generated in the reaction. The cleavage of OH groups ino methylene groups is well knowed but what about the cleavege of C=O group into a methylene group? The literature about it is very rare but some papers do confirm it's possible if using more HI and extend the time of the reflux at high temperature. So, any expert here could give their opinion? If the reduction of Methcathinone with phosphorous and iodine route could be so easy like Ephedrine reduction, following the same methods with some modifications would be a very nice, cheap and easy way to sinthesize Methamphetamine.
I'm working nowadays on 4MMC and methcathinone synthesis starting from 4-methyl propiophenone and propiophenone by bromination with HBR and H2O2 and further methylamination with CH3NH2 40% aquous solution in ethyl acetate, following recipes I've found here in BB Expert and my work were plenty sucesssfull until now. I think this route is easier for me since I have a good raw material supply. As a result I have on stock almost a kilo of pure 4MMC hydrochloride and bearing half a kilo of methcathinone hydrochloride. I think it's not interesting for me reducing methcathinone hydrochloride to racemic ephedrine hydrochloride with NABH4 in ethanol like here: https://bbforum.org/en/threads/synthesis-of-ephedrine-hydrochloride-and-chemical-analysis.9537/ to reduce later the Ephedrine to Meth in two steps. I'm wondering if is possible to do that directly, in only one step.
As I've said, surprisiling almost no data abouth methcathinone reduction to meth exists anywhere, what is a shame that force us only to especulate theoretically. Have any Expert here on this Forum enough knwoledge to clear these questions?
I have searched across the net and across BB Forum and is hard to find anything solid about it. There's a thread here in BB Forum mentioning about using Clemensen reduction to do this job, but without further details: (https://bbforum.org/en/threads/meth...-mercury-amalgam-and-hydrochloric-acid.16784/). I think Clemensen reduction will not work properly in this case cause it demands acidic environment that favor the formation of dimmers and sideproducts. Anybody here could present arguments that corroborate Clemensen Reduction works properly with amino ketones?
The literature presents some other methods to reduce carbonyl groups to methylene groups (Todd, D. (2011). The Wolff-Kishner Reduction. Organic Reactions, 378–422. doi 10.1002-0471264180.or004.08). Pd/C, and thioacetals with Raney Nickel are examples but rather unfeasible for me cause the complexity of the methods and the high cost of the raw material. So Wolff-Kishner Reduction presents a low cost, simple and efective method to reduce amino ketones without affect the amino group, since demands basic conditions. At other side, some articles say converting the ketone to a hydrazone, followed by treatment with a strong base at high temperatures, can induce rearrangements or deamination of the amino group. The question is: BOC protection of the amino group is or isn't mandatory in this case? Anybody here could present arguments that corroborate Wolff-Kishner Reduction works properly with amino ketones without amino group protection? Protect and desprotect tha amino group is a pain in the ass that would turn the process more expensive, tedious and time consuming.
The literature say HI, as a powerfull reducing agent can deoxigenate almost every substance at the right condictions. Is employed susscefully in the reduction of Ephedrine to meth, reducing the OH group to a methylene group. The methodology used is often using Red phosphorous and Iodine or H3PO2 and Iodine at reflux and temperatures between 100-160ºC. The role here is the formation of PI3 that act as a catalizer regenerating the HI from the Iodine formed from the cleavage of the OH radical into a methylene group and the H3PO2 from the H3PO3 generated in the reaction. The cleavage of OH groups ino methylene groups is well knowed but what about the cleavege of C=O group into a methylene group? The literature about it is very rare but some papers do confirm it's possible if using more HI and extend the time of the reflux at high temperature. So, any expert here could give their opinion? If the reduction of Methcathinone with phosphorous and iodine route could be so easy like Ephedrine reduction, following the same methods with some modifications would be a very nice, cheap and easy way to sinthesize Methamphetamine.
I'm working nowadays on 4MMC and methcathinone synthesis starting from 4-methyl propiophenone and propiophenone by bromination with HBR and H2O2 and further methylamination with CH3NH2 40% aquous solution in ethyl acetate, following recipes I've found here in BB Expert and my work were plenty sucesssfull until now. I think this route is easier for me since I have a good raw material supply. As a result I have on stock almost a kilo of pure 4MMC hydrochloride and bearing half a kilo of methcathinone hydrochloride. I think it's not interesting for me reducing methcathinone hydrochloride to racemic ephedrine hydrochloride with NABH4 in ethanol like here: https://bbforum.org/en/threads/synthesis-of-ephedrine-hydrochloride-and-chemical-analysis.9537/ to reduce later the Ephedrine to Meth in two steps. I'm wondering if is possible to do that directly, in only one step.
As I've said, surprisiling almost no data abouth methcathinone reduction to meth exists anywhere, what is a shame that force us only to especulate theoretically. Have any Expert here on this Forum enough knwoledge to clear these questions?
