反应详情

To 30 ml of an ethanol solution of 13.0 g of the intermediate product obtained in Preparative Example 2, viz., 2-ethylmercapto-3-ethylbenzothiazolium p-toluenesulfonate, was added 4.4 g of 3-carboethoxymethylrhodanine, while stirring the mixture at room temperature (about 20° C.), 6.1 g of triethylamine was added dropwise to the solution over a 3 minute period, and thereafter the resultant mixture was refluxed for 10 minutes. After cooling the reaction mixture, precipitates formed were recovered by filtration and recrystallized from a mixture of chloroform and ethanol to provide 1.1 g of 3-carboethoxymethyl-5-(3-ethylbenzothiazolylidene)rhodanine (melting point 250° to 252° C.).

1. additionwas added dropwise to the solution over a 3 minute period
2. temperatureAfter cooling the reaction mixture
3. customprecipitates
4. customformed
5. filtrationwere recovered by filtration
6. customrecrystallized from a mixture of chloroform and ethanol