Sodium Hydroxide → 3-(Piperazin-1-YL)-1H-indazole
Reaction equation
[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[C:3]([N:10]2[CH2:15][CH2:14][N:13](C#N)[CH2:12][CH2:11]2)=[N:2]1.[OH-].[Na+]>OS(O)(=O)=O>[N:10]1([C:3]2[C:4]3[C:9](=[CH:8][CH:7]=[CH:6][CH:5]=3)[NH:1][N:2]=2)[CH2:15][CH2:14][NH:13][CH2:12][CH2:11]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A mixture of 4-(1H-indazol-3-yl)-l-piperazinecarbonitrile (8.0 g, 40 mmol) and 25% H2SO4 (100 ml) was stirred at reflux for 4.5 hours. The reaction was cooled in an ice bath and made basic by the dropwise addition of 50% NaOH. The basic solution was extracted with ethyl acetate. The ethyl acetate was washed with H2O, dried with MgSO4, and concentrated to afford 5.2 g (73% of the desired compound, as a solid. The solid was recrystallized twice from toluene to afford 3.0 g of 3-(1-piperazinyl)-1H-indazole, m.p.=153°-155° C.
Workup
- temperatureat reflux for 4.5 hours
- temperatureThe reaction was cooled in an ice bath
- extractionThe basic solution was extracted with ethyl acetate
- washThe ethyl acetate was washed with H2O
- dry with materialdried with MgSO4
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-e1604f68eed34b07ad13635fb8e2ec0f
- Source dataset
- uspto-grants-1997_01
- Patent number
- US05591745
Reaction notes
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