反应详情

A solution of 1-(3-nitrophenyl)piperazine hydrochloride (1.80 g) in water (7 ml) was basified with anhydrous sodium carbonate (0.8 g) and the mixture evaporated to dryness in vacuo. The solid was mixed with formic acid (17 ml) and a solution of formaldehyde 36% in water (1.3 ml, ≡0.47 g CH2O) added and the mixture heated at 95°-98° for 3 h. The mixture was diluted with water (35 ml) and basified with anhydrous sodium carbonate. The suspension was extracted with ethyl acetate (2×80 ml) and the extract dried for 1 h. The mixture was filtered and the filtrate evaporated to dryness to give a dark red oil which was dissolved in ether (20 ml) and filtered. The filtrate was evaporated to dryness to give a red oil which was purified by FCC eluting with System A (500:8:1) to give an orange oil which was dried in vacuo. Upon scratching, crystallisation began and the oil was left to stand until crystallisation of the title compound was complete (1.10 g) m.p. 53°-54° C.

1. customthe mixture evaporated to dryness in vacuo
2. additionThe solid was mixed with formic acid (17 ml)
3. additiona solution of formaldehyde 36% in water (1.3 ml, ≡0.47 g CH2O) added
4. temperaturethe mixture heated at 95°-98° for 3 h
5. additionThe mixture was diluted with water (35 ml)
6. extractionThe suspension was extracted with ethyl acetate (2×80 ml)
7. customthe extract dried for 1 h
8. filtrationThe mixture was filtered
9. customthe filtrate evaporated to dryness
10. customto give a dark red oil which
11. filtrationfiltered
12. customThe filtrate was evaporated to dryness
13. customto give a red oil which
14. customwas purified by FCC
15. washeluting with System A (500:8:1)
16. customto give an orange oil which
17. customwas dried in vacuo
18. customcrystallisation
19. waitthe oil was left
20. customto stand until crystallisation of the title compound