Water → HCID 21537768, compound

Participants

Reaction Steps

To a solution of 16.1 g of 4-(o-fluorophenyl)-1,2,5,6,7,8-hexahydrobenzothieno[2,3-d]pyrimidin-2-one in 322 of dimethylformamide is added 2.88 g of 67% sodium hydride. The mixture is stirred for 1 hour at room temperature, and 22.83 g of methyl iodide in 68 ml of dimethylformamide is added thereto at 10°C. The resulting reaction mixture is stirred for 2 hours at room temperature, then poured into water and extracted with chloroform. The chloroform extracts are washed with water, dried over sodium sulfate, and the solvent is removed under reduced pressure. The residue is chromatographed on silica gel, using chloroform as an eluent. From the first fraction 2-methoxy-4-(o-fluorophenyl)-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidine is obtained as crystals having a melting point of 98° - 100°C. From the second fraction, 1-methyl-4-(o-fluorophenyl)-1,2,5,6,7,8-hexahydrobenzothieno[2,3-d]pyrimidin-2-one is obtained as crystals having a melting point of 221° - 222.5°C.

Provenance & Evidence