反应详情

Ethyl[N-(3-pyridylmethyl)-N-(methoxycarbonylethyl)carbamoyl]acetate (1.0 g) and carbon disulfide (0.2 ml) are dissolved in dimethylsulfoxide (12 ml), and thereto is added a solution of potassium hydroxide (378 mg) in water (1 ml). The mixture is stirred at room temperature for 20 minutes. A solution of cis-1,2-dichloroethylene (0.245 ml) in dimethylsulfoxide (2 ml) is added dropwise to the mixture, and the mixture is stirred at 50°-55° C. for 6 hours. After cooling, the mixture is poured into water, and the aqueous solution is extracted with ethyl acetate. The extract is washed with water, dried and then distilled to remove the solvent. The residue is purified by silica gel column chromatography (solvent, ethyl acetate) to give ethyl 2-(1,3-dithiol-2-ylidene)-2-[N-(3-pyridylmethyl)-N-(methoxycarbonylethyl)carbamoyl]acetate (429 mg) as oil.

1. stirringthe mixture is stirred at 50°-55° C. for 6 hours
2. temperatureAfter cooling
3. extractionthe aqueous solution is extracted with ethyl acetate
4. washThe extract is washed with water
5. customdried
6. distillationdistilled
7. customto remove the solvent
8. customThe residue is purified by silica gel column chromatography (solvent, ethyl acetate)