反应详情

A solution of 7.7 g of diazopropane in ether is added in portions to a solution of 28.8 g of 2,3-dihydro-6-(4-chlorophenylthio)-2-thioxo-4H-1,3,5-thiadiazin-4-one in 250 ml of tetrahydrofuran at 22° C. The solvent is distilled off, the residue is taken up in a small amount of methanol, and the precipitate is filtered off under suction, washed with methanol and dried. 21.9 g of 3-propyl-6-(4-chlorophenylthio)-2-thioxo-1,3,5-thiadiazin-4-one are obtained in the form of yellow crystals of melting point 151°-152° C.

1. distillationThe solvent is distilled off
2. filtrationthe precipitate is filtered off under suction
3. washwashed with methanol
4. customdried