反应详情

The isatin derivative (70 g) obtained in the above item (i), 200 ml of acetic acid and 0.8 ml of concentrated sulfuric acid were charged in a 500 ml two-neck flask and the mixture was stirred at room temperature. Then, 50 ml of 30% hydrogen peroxide was added dropwise to the mixture. After the completion of dropping, the mixture was stirred at 60° to 65° C. for one hour and a half and then cooled. The deposit was filtered, washed with water and dried under vacuum to give 35 g of a derivative of isatoic acid anhydride represented by the following formula (20): ##STR24##

1. additionwere charged in a 500 ml two-neck flask
2. stirringthe mixture was stirred at 60° to 65° C. for one hour
3. temperaturea half and then cooled
4. filtrationThe deposit was filtered
5. washwashed with water
6. customdried under vacuum