反应详情

温度

100 °C

A solution of 2.3 g 3-difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid (2-hydroxy-1-methyl-ethyl)-amide (10.0 mmol, prepared as described in example P5a) and 2.6 g 2-bromo-3-chloro-5-trifluoromethyl-pyridine (10 mmol) in dimethylformamide (30 ml) is treated at ambient temperature with 2.8 g potassium carbonate (20 mmol). The resulting suspension is stirred at 100° C. for 3 hours, cooled to ambient temperature, poured onto water (200 ml) and extracted with ethyl acetate (2×100 ml). The combined ethyl acetate layers are washed with water (20 ml) and dried over Na2SO4. After removal of the solvent the residue (4.2 g in the form of an oil) is purified by flash chromatography over silica gel (eluent: cyclohexane/ethyl acetate 3:7). 1.4 g (34% of theory) of 3-difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid [2-(3-chloro-5-trifluoromethyl-pyridin-2-yloxy)-1-methyl-ethyl]-amide (compound 1.239) is obtained in form of a solid (mp. 115-118° C.).

1. temperaturecooled to ambient temperature
2. additionpoured onto water (200 ml)
3. extractionextracted with ethyl acetate (2×100 ml)
4. washThe combined ethyl acetate layers are washed with water (20 ml)
5. dry with materialdried over Na2SO4
6. customAfter removal of the solvent the residue (4.2 g in the form of an oil)
7. customis purified by flash chromatography over silica gel (eluent: cyclohexane/ethyl acetate 3:7)