反应详情

To a solution prepared by stirring a mixture of selenium dioxide (6.2 g.), dioxane (320 ml.) and water (6.4 ml.) at 50° to 60° C. was added ethyl 2-(2-propanesulfonylamino-1,3-thiazol-4-yl)acetate, which can be represented as ethyl 2-(2-propanesulfonylimino-2,3-dihydro-1,3-thiazol-4-yl)acetate, (16.3 g.), and the mixture was refluxed for 1 hour. To the mixture was added selenium dioxide (0.6 g.), and the mixture was further refluxed for 30 minutes and selenium dioxide (0.3 g.) was added thereto, and then the mixture was further refluxed for 30 minutes. After the reaction, the reaction mixture was filtered, and then dioxane was distilled off. The residue was dissolved in ethyl acetate under heating and then treated with activated charcoal. The solvent was distilled off, and the residue was washed with a small amount of ethyl acetate and diethyl ether in turn and dried to give ethyl 2-(2-propanesulfonylamino-1,3-thiazol-4-yl)glyoxylate, which can be represented as ethyl 2-(2-propanesulfonylimino-2,3-dihydro-1,3-thiazol-4-yl)glyoxylate, (12.5 g.), mp 132° to 134° C.

1. customTo a solution prepared
2. temperaturethe mixture was refluxed for 1 hour
3. temperaturethe mixture was further refluxed for 30 minutes
4. temperaturethe mixture was further refluxed for 30 minutes
5. customAfter the reaction
6. filtrationthe reaction mixture was filtered
7. distillationdioxane was distilled off
8. dissolutionThe residue was dissolved in ethyl acetate
9. temperatureunder heating
10. additiontreated with activated charcoal
11. distillationThe solvent was distilled off
12. washthe residue was washed with a small amount of ethyl acetate and diethyl ether in turn
13. customdried