反应详情

N,O-dimethylhydroxylamine hydrochloride (1.30 g) was added to an dimethylformamide (32 mL) solution that contained 1-methyl-1H-pyrazol-5-carboxylic acid (1.21 g), O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (4.38 g) and diisopropylethylamine (3.34 mL) at a room temperature, and the obtained solution was then stirred for 2 hours. Thereafter, water was added to the reaction solution, and the obtained mixture was then extracted with ethyl acetate. The organic layer was washed with water and a saturated saline, and was then dried over anhydrous magnesium sulfate, followed by vacuum concentration. The residue was purified by column chromatography (silica gel cartridge, chloroform:methanol=100:0 to 95:5), so as to obtain the title compound (1.03 g) in the form of a yellow oily substance.

1. customat a room temperature
2. extractionthe obtained mixture was then extracted with ethyl acetate
3. washThe organic layer was washed with water
4. dry with materiala saturated saline, and was then dried over anhydrous magnesium sulfate
5. concentrationfollowed by vacuum concentration
6. customThe residue was purified by column chromatography (silica gel cartridge, chloroform:methanol=100:0 to 95:5)