N-((3R,4R)-1-benzyl-4-methylpiperidin-3-yl)-N-methyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine

N-((3R,4R)-1-benzyl-4-methylpiperidin-3-yl)-N-methyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine is an important pharmaceutical intermediate used for the synthesis of tofacitinib. Tofacitinib is a Janus kinase (JAK) inhibitor drug used to treat rheumatoid arthritis and psoriatic arthritis.

N-((3R,4R)-1-benzyl-4-methylpiperidin-3-yl)-N-methyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine is prepared by the reaction of 4-chloropyrrolopyrimidine and (3R,4R)-1-benzyl-N,4-dimethylpiperidin-3-amine dihydrochloride. The specific synthesis steps are as follows:
The reaction flask is added to sodium hydroxide (10.0g, 250mmol), water and dissolved, make 10% of the solution, adding acetone to another reaction bottle 80g, the toluene sulfonyl chloride (38.13g, 200mmol), after stirring to dissolve, then adding 4-chloro pyrrolo pyrimidine (15.36g, 100mmol), stirring mixing, cooling to 0 °C the following, dropping sodium hydroxide solution, the temperature is controlled at 5 °C the following, completion of the dropping, heating, to control the temperature to 20-30 °C stirring within the range of the reaction, to the reaction end after TLC monitoring, filtering, to get the product into the reaction bottle, adding water 200 ml, (3R, 4R)-cis-1-benzyl-4-methyl-3-methylamino-piperidine dihydrochloride (21.33g, 105mmol), stirring to dissolve, then adding potassium carbonate (82.93g, 600mmol), stirring, heating 95 °C, TLC monitoring to the reaction end of the, cooling to 45-55°C, by adding acetonitrile, preserving heat and stirring 1 hour, cooling to room temperature, crystallization, filtration, washing, the wet articles in added in the reaction bottle, adding dimethyl sulfoxide 250 ml, by adding 50% sodium hydroxide solution to 250 ml, stirring and heating 95 °C, TLC monitoring to the reaction end rear, layered, water extraction once with dimethyl sulfoxide, merger dimethyl asian sulphone level, cooling to 75-85°C, water slowly under stirring, the stirring cooling to room temperature, filtering, washing, 50% ethanol washing, filtering, drying, be [(3R, 4R) - 1 benzyl-4-methyl-piperidin-3-yl]-methyl-(7H-pyrrolo [2,3-d] pyrimidin-4-yl)-amine 25.83g, yield 77.0%, optical purity 99.8% (HPLC method).