Phosphorus sulfide (P2S5) → 5-(2-Chlorophenyl)-7-ethyl-1,3-dihydro-2H-thieno[2,3-e]-1,4-diazepine-2-thione

Participants

Reaction Conditions

Reaction Steps

[a] To a solution of 40 g of 5-o-chlorophenyl-7-ethyl-1,2-dihydro-3H-thieno[2,3-e][1,4]diazepin-2-one in 200 ml of pyridine is added 32 g of phosphorus pentasulfide, and the mixture is stirred at 60°C for 1 hour. After allowing to cool, the reaction mixture is poured into 2 liters of ice water with stirring. The precipitate formed is collected with suction filtration and washed with water. The precipitate is dissolved in chloroform, and the solution is washed with a saturated sodium bicarbonate and washed with water. The chloroform layer is dried over sodium sulfate and concentrated in vacuo. The residue is recrystallized from a mixture of ethanol and chloroform to give 31.4 g of 5-o-chlorophenyl-7-ethyl-1,2-dihydro-3H-thieno[2,3-e][1,4]diazepine-2-thione as yellowish crystals melting at 198°-199°C (decomposition).

Provenance & Evidence