反应详情

A mixture of 250 ml of 100% strength by weight nitric acid and 350 ml of concentrated sulphuric acid was added dropwise with stirring to an initial charge of 317 g of the product from Example 15a. The mixture was stirred for 2 hours at 55° C. The mixture was then cooled and poured into ice-water. The product was extracted with methylene chloride, washed until neutral with sodium hydrogen carbonate solution, dried, and freed on a rotary evaporator from readily volatile constituents. The yield was 339 g (=94% of theory), the melting point was 101° to 103° C.

1. additionwas added dropwise
2. stirringThe mixture was stirred for 2 hours at 55° C
3. temperatureThe mixture was then cooled
4. extractionThe product was extracted with methylene chloride
5. washwashed until neutral with sodium hydrogen carbonate solution
6. customdried
7. customfreed on a rotary evaporator from readily volatile constituents