2629-91-6

Upstream product

• 219915-67-0 4-methyl-N’-(2-oxo-1-phenyl-2-(piperidin-1-yl)ethylidene)benzenesulfono hydrazide 
• 110-89-4 piperidine 
• 15206-55-0 methyl 2-oxo-2-phenylacetate 
• 3626-62-8 2-phenyl-1-(1-piperidinyl)ethanone 
• 101-41-7 benzeneacetic acid methyl ester 

Downstream Products

• 298-59-9 methylphenidate hydrochloride 
• 19262-68-1 dexmethylphenidate hydrochloride 
• 113-45-1 dl-threo-methylphenidate 
• 113-45-1 methyl (R*)-2-phenyl-2-((S*)-piperidin-2-yl)acetate 

Relevant academic research and scientific papers

Preparation method of dexmethylphenidate

The invention relates to a new synthetic route of dexmethylphenidate. Methyl phenylacetate serves as a raw material, and the dexmethylphenidate is synthesized at high yield through four steps of an amidation reaction, a diazotization reaction, a cyclization reaction and a rearrangement reaction. The preparation method of the dexmethylphenidate is high in yield, low in cost, environmentally friendly, easy to operate and suitable for industrialization.

IMPROVEMENTS IN OR RELATING TO ORGANIC MATERIAL

The invention provides a method for the preparation of an intermediate for use in synthesizing a lower alkyl phenidate compound of formula (I), wherein each R1 independently represents an optionally substituted aryl, heteroaryl, alkyl, cycloalkyl, alkoxy, aryloxy, acyl, carboxyl, hydroxyl, halogen, amino, nitro, sulfo or sulfhydryl group, R2 represents a hydrogen atom or a lower alkyl group, n represents an integer from 1 to 5 and m represents an integer from 1 to 3 or a pharmaceutically acceptable salt thereof; which method comprises the steps of: (a) flowing a tosylhydrazone compound of formula (IV), wherein R1, n and m are as defined above in relation to the methylphenidate of formula (I), an organic base and an organic solvent into a fluidic network; and (b) reacting the tosylhydrazone compound of formula (IV) and the base in the fluidic network under thermal and/or photochemical conditions to form a transient diazoamide compound of formula (V), wherein R1, n and m are as defined above in relation to the methylphenidate of formula (I).