反应详情

Methyl 1-(3-pyridylmethyl)-5-(1,3-dithiol-2-ylidene)-4,6-dioxopiperidine-3-carboxylate (244 mg) obtained in Example 27 is dissolved in methanol (15 ml), and thereto is added a 10% sodium hydroxide solution (2 ml). The mixture is refluxed for 2 hours. The mixture is poured into water, and extracted with chloroform. The extract is washed with water, dried and then distilled to remove the solvent. The residue is recrystallized from a mixture of ethyl acetate and and n-hexane to give 1-(3-pyridylmethyl)-3-(1,3-dithiol-2-ylidene)-2,4-dioxopiperidine (114 mg, 66.1%) as yellow plates, m.p. 131.5°-133° C.

1. temperatureThe mixture is refluxed for 2 hours
2. extractionextracted with chloroform
3. washThe extract is washed with water
4. customdried
5. distillationdistilled
6. customto remove the solvent
7. customThe residue is recrystallized from a mixture of ethyl acetate and and n-hexane