反应详情

温度

130 °C

A mixture of 4-benzoyl-3-n-butoxy-5-sulfamylbenzoic acid (0.94 g), 98% aqueous hydrazine hydrate (1.5 ml), potassium hydroxide (0.5 g) in water (1.0 ml) and diethylene glycol (6.5 ml) is stirred at about 130° C. for 3 hours. The temperature is then slowly raised to 215° C. allowing volatile material to distil off. The stirring at 215° C. is continued for a further 2-3 hours until the nitrogen evolution has ceased. After cooling and dilution with water (10 ml), the resulting solution is acidified with conc. hydrochloric acid (1 ml). The resulting precipitate is collected by filtration and washed with water. After drying and recrystallization twice from aqueous ethanol, 4-benzyl-3-n-butoxy-5-sulfamylbenzoic acid is obtained with a melting point of 228°-229° C.

1. temperatureThe temperature is then slowly raised to 215° C.
2. customto distil off
3. waitThe stirring at 215° C. is continued for a further 2-3 hours until the nitrogen evolution
4. temperatureAfter cooling
5. filtrationThe resulting precipitate is collected by filtration
6. washwashed with water
7. customAfter drying
8. customrecrystallization twice from aqueous ethanol