反应详情

温度

180 °C

Sodium hydroxide (251.9 g, 6.30 mol) was added in portions to 4-sulphophthalic acid (50% in water, 258.4 g, 0.525 mol) in a steel vessel accompanied by stirring. After the addition of approx. one third NaOH the increasingly more viscous mixture was heated to 180° C. Once the addition had ended the mixture was stirred for a further 2 h at 200° C. During cooling, the residue was dissolved in water (1000 ml). Conc. hydrochloric acid (620 ml, pH=1) was added accompanied by ice cooling. The solution was extracted with ethyl acetate (5×400 ml). The combined organic phases were dried over Na2SO4, filtered and concentrated on the rotary evaporator. The slightly yellow solid was recrystallized from ethyl acetate. 68.64 g (0.377 mol; 72% yield) of a white solid was obtained.

1. additionAfter the addition
2. temperatureincreasingly more viscous mixture
3. additionOnce the addition
4. stirringwas stirred for a further 2 h at 200° C
5. temperatureDuring cooling
6. extractionThe solution was extracted with ethyl acetate (5×400 ml)
7. dry with materialThe combined organic phases were dried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated on the rotary evaporator
10. customThe slightly yellow solid was recrystallized from ethyl acetate
11. custom68.64 g (0.377 mol; 72% yield) of a white solid was obtained