Triethylamine → Ethyl 4-hydrazinyl-2-(methylthio)-5-oxo-8-phenyl-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidine-6-carboxylate

Participants

Reaction Steps

To a solution of ethyl 4-chloro-2-(methylthio)-5-oxo-8-phenyl-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidine-6-carboxylate (21 g, 55.57 mmol) in 1,4-dioxane (400 mL) was added triethylamine (8.52 mL, 61.13 mmol) followed by hydrazine hydrate (3.06 g, 61.13 mmol). The reaction mixture was stirred at room temperature for 5-6 h. Upon completion of the reaction, dioxane was removed under reduced pressure and water (250 mL) was added to the reaction mixture. The reaction mixture was then extracted with dichloromethane (200 mL×3). The combined organic layers was washed with water (500 mL) followed by brine (500 mL), dried over anhydrous Na2SO4, filtered and concentrated to give crude ethyl 4-hydrazinyl-2-(methylthio)-5-oxo-8-phenyl-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidine-6-carboxylate (20 g) which was used in the next step without purification. LCMS [M+H]: 374

Provenance & Evidence