反应详情

A solution of 150 g (0.9 mol) of dimethylnitrophenol in 700 ml of dichloromethane is cooled to −15° C. 181 ml of pyridine are added. 308.8 g (1.09 mol) of trifluoromethanesulphonic anhydride are then metered in dropwise over a period of 2 h in such a way that the reaction temperature does not exceed −5° C. Then, at a temperature of −5° C., 150 ml of water are added. The organic phase is extracted successively with HCl (1 molar, about 300 ml) and water (twice), each at 3-5° C. The solvent is removed in vacuo, and the residue is stirred with petroleum ether. The precipitate is filtered off with suction. A further fraction is obtained by cooling the mother liquor. Yield: 232 g (85%)

1. customof 2 h
2. customdoes not exceed −5° C
3. extractionThe organic phase is extracted successively with HCl (1 molar, about 300 ml) and water (twice), each at 3-5° C
4. customThe solvent is removed in vacuo
5. filtrationThe precipitate is filtered off with suction
6. customA further fraction is obtained
7. temperatureby cooling the mother liquor