About the methylphenidate synthesis way

[untryrgos]

Hello guys, I want to share some experience about Ritalin.I apologize for my poor English and less experience.Recently I successfully synthesis methylphenidate from Ritalin acid.It is an easy way.
First,I brought 75 grams Ritalin acid from China because it is legal substance and none will notice it.
Then I prepared 500ml methanol-hcl solution using a simple way, just passed hydrogen chloride into methanol until saturated.Don't use the water solution because it will reduced yield or the reaction will not happen Make the environment dry is important.You can use the molecular sieve to dry out these.
Mixed these together in a bottle with reflux condenser with strong stirring.Heating the rm 40-45 degree celsius, because higher temperature will let methanol and hcl react and increase water.The Ritalin acid only dissolves part, but don't worry that. The reaction will happen and dissolve all acid.
After two days reaction.The salt will appear.Put the rm and salt into a warm place to evaporation all of solvent.Dry rm and recrystallize use water .Don't heat methylphenidate to dry it.
At the appropriate dose, the effect is smooth and peaceful maybe because I have ADHD.

 

[HewHiSt]

hey, how can i find a ritalin acid supplier in China ?

 

[untryrgos]

I found a Wuhan company.A few companies can produce it.You can find them on a site called chemical book.I also find they selling it on Alibaba, just search cas19395-41-6 (α-phenylpiperidine-2-acetic acid).

 

[HewHiSt]

Thanks mate

 

[ChemistryHobby]

I plan to do as you have done.
To make the HCl gas, I plan to use 20% solution HCl plus CaCl2.
I cannot find a higher concentration of HLC.
My question is will the gas be dry enough?
I guess i will have to dry it again through a drying tube of CaCl2??
Do I really have to use my 20% solution to make another solution more concentrated by bubbling HCL gas through it?

All HCL generators I see online seem to need 35% or greater solution of HCL with CaCl2.



How do I know when the methanol is full saturated with HCL?
I can check a PH? so it change colour?

You use the molecular sieve to dry out the methanol before bubbling through the HCL or after, or even during?

Thanks,,

 

[GnarleyBarley]

If you look up a common synthesis of ritalinic acid, you will see it produces 20:80 ratio threo to erythro isomer. What do you believe the chance of the ritalinic acid from china is produced by that method? Because obviously ritalinic acid is not the cheapest and getting only 20% of threo (of which only 50% will be the good dextro isomer) will obviously be problematic.

Edit:
https://doi.org/10.1021/jm00142a021
It is the 4-hydroxy version but same starting material without the 4-hydroxy should still lead to the 20:80 ratio.

Again only problematic if the ritalinic acid china produces is produced by this method. If they use another method which produces 50:50 threo:erythro, then no problem.

Also just so you know. SOCL2 can be used with methanol, instead of anyhydrous HCL