4-Chloro-2-(methylthio)pyrimidine-5-carboxylic acid ethyl ester → 7-Methylthio-4-oxo-2-(2-propoxyphenyl)-3,4-dihydropyrimido[4,5-d]pyrimidine

Participants

Reaction Conditions

Reaction Steps

2-Propoxybenzamidine (from sodium, 0.3 g, in ethanol, 50 ml, and 2-propoxybenzamidine hydrochloride, 2.77 g) was dissolved in 2-propanol (20 ml) and the resulting cooled (2° C.) solution was added to a cooled (2° C.) solution of ethyl 4-chloro-2-methylthio-5-pyrimidine carboxylate (2 g) in 2-propanol (30 ml). The reaction mixture was stirred at 2° C. for 2 hours and was then left overnight at ambient temperature to yield a white crude product, 1.18 g, m.p. 179°-181° C. Recrystallisation from ethanol yielded the title compound, 0.92 g, m.p. 186°-187° C.

Provenance & Evidence