反应详情

To a chilled solution of spiro(cyclopentane-1,1'-indan)-3'-one (16.7 g; 0.09 moles) in conc. sulphuric acid (100 ml) there are added in portions under agitation a solution of potassium nitrate (10 g) in conc. sulphonic acid (30 ml). The temperature should not exceed 10°-15° C. The mixture is kept cold for 1 hour and then put on ice. The crude product is sucked off and thoroughly washed with water. After drying there are obtained 1917 g of a yellow powder (yield 95%), mp. 104° C. A sample is recrystallized from N-hexane and melts at 110° C.

1. customexceed 10°-15° C
2. washthoroughly washed with water
3. customAfter drying there