反应详情

温度

0 °C

To a 0° C. solution of 4-nitro-2-(2-trimethylsilanyl-ethoxymethyl)-2H-pyrazole-3-carboxylic acid, ethyl ester (10 g, 31.7 mmol) in tetrahydroftiran (200 mL) was added methanol (24 mL) followed by sodium borohydride (9.59 g, 8 eq) in one portion. The resulting mixture was stirred at 0° C. for 20 minutes. The reaction mixture was then added to a mixture of saturated aqueous ammonium chloride solution (600 mL) and ethyl acetate (800 mL) in an ice-bath. A solution of 4 N HCl was added with stirring at 0° C. to adjust the pH of the aqueous layer to about 4. The organic layer was separated and washed with brine (1×500 mL), dried over magnesium sulfate, filtered and concentrated to give the title compound (7.76 g) as a reddish oil. M+=273.

1. stirringwith stirring at 0° C.
2. customThe organic layer was separated
3. washwashed with brine (1×500 mL)
4. dry with materialdried over magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated