反应详情

To 250 ml of cold (-20° C.) concentrated sulfuric acid is added with stirring 4-methylacetophenone (40 g, 300 mmoles). When the first addition is complete, a mixture of 25.5 ml (36.3 g, 300 mmoles) of 70% nitric acid and 300 g of 20% fuming sulfuric acid is added dropwise over 40 minutes. The temperature remains below -15° C. The mixture is stirred for an additional 30 minutes and then poured onto ice. The solids are filtered, washed with water and then with hexane. The solids are dissolved in dichloromethane and washed with 10% sodium bicarbonate solution and finally with saturated sodium chloride solution. The organic phase is dried, charcoaled, concentrated and diluted with hexane, whereupon the product, 4-methyl-3-nitroacetophenone, crystallizes, m.p. 61°-62° C.

1. additionWhen the first addition
2. additionis added dropwise over 40 minutes
3. customremains below -15° C
4. additionpoured onto ice
5. filtrationThe solids are filtered
6. washwashed with water
7. dissolutionThe solids are dissolved in dichloromethane
8. washwashed with 10% sodium bicarbonate solution and finally with saturated sodium chloride solution
9. customThe organic phase is dried
10. concentrationconcentrated
11. additiondiluted with hexane, whereupon the product, 4-methyl-3-nitroacetophenone
12. customcrystallizes