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Hey guys. I have ritalinic acid. What do I need to make metylphenidate and etylphenidate? I'm a complete newbie, could you please explain me step by step? Would be really grateful
- By kotkata
Is there a protocol or beginner's guide or recipe of some sort to convert ritalinic acid to methylphenidate?
To my understanding it's not rocket, but I'm a bit confused how to get methylphenidate from ritalinic acid.
To my understanding it's not rocket, but I'm a bit confused how to get methylphenidate from ritalinic acid.
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Hello everybody! Replying for dupskoslonia, I add recipe for methylphenidate hydrochloride from dl-threo-ritalinic acid (which is easy avaliable in China, price for 1 kg is about 600-700$). I made dl-threo-methylphenidate hydrochloride a few times of this recipe and it's absolutely easy and perfect. 1 kg of methylphenidate hydrochloride, you can do in 20L single-neck flask (you don't need reactor).
125g (0.57 mol) of dl-threo-ritalinic acid added to reactor. Then added 256.7g (5 mol) of dimethyl carbonate and 27.5g methanol. Then at room temperature with mechanical stirrer (magnetic stirrer is not good to this operation) slowly added 762g of 96% or more of sulphuric acid (temperature <80oC). The jacket temperature was increased to 85oC (target internal temperature about 70oC). The reaction was stirred overnight (at least 16 hours) at a jacket temperature of 85oC.
The resulting mixture was then cooled to 15-20oC. To the resulting mixture was then added 250g of isopropyl acetate followed by addition of 18% NaOH (212.5g, 1.68 mol), while maintaining the temperature below at 30oC. Then, the mixture stirred for about 15 minutes. The layers were allowed to settle for about 20 minutes and the lower, caustic (aqueous) layer separated and discarded. To the organic layer was then added deionized water (187.5g) and the resulting mixture stirred for about 20 minutes. The layers were allowed to settle for about 20 minutes and the lower, water layer seperated and discarded. The organic layer, contain dl-threo-methylphenidate.
A second reactor was charged with the solution of 37% HCl (59g, 1.05 mol) and IPA (250g). The internal temperature of the solution was adjusted to 55oC. To this reactor was then added the organic layer containing dl-threo-methylphenidate, prepared in STEP1, via addition funnel over 90 minutes, while maintaining the temperature at 55oC. Then the mixture was cooled to 10-15oC and stirred for 30 minutes. The resulting suspension was filtered through a Buchnner funnel and the wet cake washed with IpOAc (125g). Achieved about 110-125g of dl-threo-methylphenidate hydrochloride (exactly the same isomer like in pharmacy).
125g (0.57 mol) of dl-threo-ritalinic acid added to reactor. Then added 256.7g (5 mol) of dimethyl carbonate and 27.5g methanol. Then at room temperature with mechanical stirrer (magnetic stirrer is not good to this operation) slowly added 762g of 96% or more of sulphuric acid (temperature <80oC). The jacket temperature was increased to 85oC (target internal temperature about 70oC). The reaction was stirred overnight (at least 16 hours) at a jacket temperature of 85oC.
The resulting mixture was then cooled to 15-20oC. To the resulting mixture was then added 250g of isopropyl acetate followed by addition of 18% NaOH (212.5g, 1.68 mol), while maintaining the temperature below at 30oC. Then, the mixture stirred for about 15 minutes. The layers were allowed to settle for about 20 minutes and the lower, caustic (aqueous) layer separated and discarded. To the organic layer was then added deionized water (187.5g) and the resulting mixture stirred for about 20 minutes. The layers were allowed to settle for about 20 minutes and the lower, water layer seperated and discarded. The organic layer, contain dl-threo-methylphenidate.
A second reactor was charged with the solution of 37% HCl (59g, 1.05 mol) and IPA (250g). The internal temperature of the solution was adjusted to 55oC. To this reactor was then added the organic layer containing dl-threo-methylphenidate, prepared in STEP1, via addition funnel over 90 minutes, while maintaining the temperature at 55oC. Then the mixture was cooled to 10-15oC and stirred for 30 minutes. The resulting suspension was filtered through a Buchnner funnel and the wet cake washed with IpOAc (125g). Achieved about 110-125g of dl-threo-methylphenidate hydrochloride (exactly the same isomer like in pharmacy).