反应详情

To a solution of 100 g (0.7 mol) of 2-chloro-4-fluorotoluene in 250 ml of concentrated H2SO4 is added portion-wise 85 g (0.875 mol) of KNO3 at 0° C. (addition of the whole amount of KNO3 is finished in about 1 hour). The reddish mixture is slowly warmed-up at room temperature overnight and quenched over crushed ice and extracted with EtOAc. The organic layers are combined, dried over MgSO4 and concentrated. The crude oil is then purified over a large silica plug (eluent: 97/3 hexanes/EtOAc) to afford 2-chloro-4-fluoro-5-nitrotoluene as a pale yellow oil that solidifies upon standing. 1H NMR (CDCl3, 400 Mz): 7.97 (d, J=8.0 Hz, 1H), 7.32 (d, J=10.4 Hz, 1H), 2.43 (s, 3H).

1. customquenched
2. customover crushed ice
3. extractionextracted with EtOAc
4. dry with materialdried over MgSO4
5. concentrationconcentrated
6. customThe crude oil is then purified over a large silica plug (eluent: 97/3 hexanes/EtOAc)