反应详情

A mixture of 5 g. of N-(N,N-diphenylcarbamoyl)-2-phenylethenesulfonamide and 10.3 g. of ethyl isonipecotate in 20 ml. of N,N-dimethylformamide is maintained at ca. 90° C. for 40 minutes. The mixture is cooled to ambient temperature, diluted with ether, and then it is extracted with water. The water extract is acidified using concentrated hydrochloric acid, and then it is extracted with methylene chloride. The dried methylene chloride is evaporated to dryness in vacuo leaving a viscous oil. The oil is redissolved in a small volume of tetrahydrofuran, absorbed onto a column of silica gel, and then eluted from the column with an excess of the same solvent. The solvent is evaporated in vacuo, and the residue is dissolved in 50 ml. of 0.5N sodium hydroxide solution. After 1 hour it is re-precipitated by acidification, and recovered by vacuum filtration in the form of white crystals. It is then dissolved in a mixture of 100 ml. of acetone and 100 ml. of tetrahydrofuran, and the solution is concentrated slowly to effect precipitation of the product. The solid is filtered off, and then triturated with acetone to give pure N-([4-carboxypiperidino]carbonyl)-2-phenylethenesulfonamide, m.p. 179°-181° C.

1. additionA mixture of 5 g
2. extractionit is extracted with water
3. extractionThe water extract
4. extractionit is extracted with methylene chloride
5. customThe dried methylene chloride is evaporated to dryness in vacuo
6. customleaving a viscous oil
7. customabsorbed onto a column of silica gel
8. washeluted from the column with an excess of the same solvent
9. customThe solvent is evaporated in vacuo
10. dissolutionthe residue is dissolved in 50 ml
11. customAfter 1 hour it is re-precipitated by acidification
12. filtrationrecovered by vacuum filtration in the form of white crystals
13. dissolutionIt is then dissolved in a mixture of 100 ml
14. concentrationof tetrahydrofuran, and the solution is concentrated slowly
15. customprecipitation of the product
16. filtrationThe solid is filtered off
17. customtriturated with acetone