反应详情

9.35 g (167 mmol) of iron powder are added to a solution of 3.00 g (16.8 mmol) of 4-nitro-1H-pyrrolo[2,3-b]pyridine 7-oxide (from example (XVI) in 225 ml of acetic acid, and the mixture is heated under reflux for 2 hours. The crude mixtures of two such batches are combined and jointly worked up further. The solid is separated off and washed with 50 ml of acetic acid and 100 ml of tetrahydrofuran. Using a rotary evaporator, the filtrate is concentrated to dryness. The residue is diluted with 50 ml of water and the solution is made alkaline using 45% strength sodium hydroxide solution. Dichloromethane is then added, and the mixture is filtered off with suction through kieselguhr. The filtrate is extracted six times with in each case 100 ml of dichloromethane and the organic phase is dried over sodium sulfate and evaporated to dryness using a rotary evaporator. The residue is dried under high vacuum. For further purification, the residue is triturated with tetrahydrofuran and the solid is filtered off with suction. The filtrate is concentrated and the residue is taken up in dichloromethane, dried and concentrated.

1. temperaturethe mixture is heated
2. temperatureunder reflux for 2 hours
3. customThe solid is separated off
4. washwashed with 50 ml of acetic acid and 100 ml of tetrahydrofuran
5. customa rotary evaporator
6. concentrationthe filtrate is concentrated to dryness
7. additionThe residue is diluted with 50 ml of water
8. additionDichloromethane is then added
9. filtrationthe mixture is filtered off with suction through kieselguhr
10. extractionThe filtrate is extracted six times with in each case 100 ml of dichloromethane
11. dry with materialthe organic phase is dried over sodium sulfate
12. customevaporated to dryness
13. customa rotary evaporator
14. customThe residue is dried under high vacuum
15. customFor further purification
16. customthe residue is triturated with tetrahydrofuran
17. filtrationthe solid is filtered off with suction
18. concentrationThe filtrate is concentrated
19. customdried
20. concentrationconcentrated