Phosgene → 3-(2,6-difluorophenyl)-7-methylthio-3,4-dihydro-1-methylpyrimido[4,5-d]pyrimidin-2(1H)-one

Participants

Reaction Steps

A stirred solution, cooled in ice, of 0.7 ml (1.3 mmol) of phosgene (20% in toluene) in 5 ml of tetrahydrofuran was treated dropwise with a solution of 210 mg (0.71 mmol) of 5-(2,6-difluorophenyl)aminomethyl-4-methylamino-2-methylthiopyrimidine and 0.2 ml (1.4 mmol) of triethylamine in 5 ml of tetrahydrofuran. The mixture was stirred for 1 hour. To the mixture were added 20 ml of tetrahydrofuran and 20 ml of saturated aqueous ammonium chloride solution and the phases were separated. The organic phase was dried over magnesium sulfate, filtered and evaporated to give 200 mg (87%) of 3-(2,6-difluorophenyl)-7-methylthio-3,4-dihydro-1-methylpyrimido[4,5-d]pyrimidin-2(1H)-one as a white solid. [Mass spectrum (ESI) MH+ =323].

Provenance & Evidence