반응 #349524

반응 방정식

end product

8-Chloro-5,6-dihydro-4-oxo-6-phenyl-4H-pyrazolo[1,5-a][1,4]benzodiazepine-2-carboxaldehyde

EtOH

hydrazine-hydrate

→

8-Chloro-2-methyl-5,6-dihydro-4-oxo-6-phenyl-4H-pyrazolo[1,5-a][1,4]benzodiazepine

용매

THF hexane

반응 조건

후처리

1. 1
   온도The reaction was heated
2. 2
   온도to reflux for 17 hours
3. 3
   온도cooled
4. 4
   농축concentrated in vacuo
5. 5
   workup.ADDITIONpotassium t-butoxide added
6. 6
   온도the mixture heated
7. 7
   온도to reflux for 8 hours
8. 8
   workup.ADDITIONThe reaction was poured over ice and brine and toluene
9. 9
   workup.ADDITIONadded
10. 10
    기타The toluene phase was separated
11. 11
    건조dried over Na2SO4
12. 12
    추출The aqueous phase was extracted well with CH2Cl2
13. 13
    건조the combined extracts dried over Na2SO4
14. 14
    농축concentrated
15. 15
    기타the crude product recrystallized from THF/hexane
16. 16
    기타to give the desired end product, mp 258°-261°
17. 17
    기타was obtained as colorless crystals

실험 절차

To a solution of 3.43 g. (10.15 mmol) of the end product of Example 15 in 60 ml. of absolute EtOH, was added 12 ml. of hydrazine-hydrate. The reaction was heated to reflux for 17 hours, then cooled and concentrated in vacuo. The residue was taken up in 60 ml. toluene; 1.0 g. potassium t-butoxide added and the mixture heated to reflux for 8 hours, then cooled to room temperature and stirred for 9 hours. The reaction was poured over ice and brine and toluene added. The toluene phase was separated and dried over Na2SO4. The aqueous phase was extracted well with CH2Cl2 and the combined extracts dried over Na2SO4. The dried solutions were combined and concentrated and the crude product recrystallized from THF/hexane to give the desired end product, mp 258°-261°. An analytical sample was prepared by an additional recrystallization from THF/hexane and was obtained as colorless crystals: mp 259°-261°.

출처