Phosgene → 3-(2-methylphenyl)-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 containing 189 mg (0.69 mmol) of 5-(2-methylphenyl)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. The phases were separated and the organic phase was dried over magnesium sulfate, filtered and evaporated to give 210 mg (100%) of 3-(2-methylphenyl)-7-methylthio-3,4-dihydro-1-methylpyrimido[4,5-d]pyrimidin-2(1H)-one as a cream-colored solid. [Mass spectrum (ESI) MH+ =301].

Provenance & Evidence