Hydrazine → HCID 178452252, compound

HRID 1157806Notes

Reaction equation

HRID 1157806 reaction equation
O=[C:2]([C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][N:18]=1)[CH2:3][N:4]1[CH2:9][CH2:8][N:7]([C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])[CH2:6][CH2:5]1.COC(OC)[N:26]([CH3:28])C.[NH2:31]N>>[N:18]1[CH:19]=[CH:20][CH:21]=[CH:22][C:17]=1[C:2]1[C:3]([N:4]2[CH2:9][CH2:8][N:7]([C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])[CH2:6][CH2:5]2)=[CH:28][NH:26][N:31]=1

Participants

4

Reactant 3

HCID 9321HydrazineHCID 78373Dimethylformamide dimethyl acetalHCID 68689149HCID 68689149, compound

Product 1

HCID 178452252HCID 178452252, compoundYield 38.1%

Procedure

Part B: A solution of tert-butyl 4-(2-oxo-2-(pyridin-2-yl)ethyl)piperazine-1-carboxylate (1.46 g, 4.78 mmol) and N,N-dimethylformamide dimethyl acetal (10.00 mL, 75 mmol) was heated at reflux for 5 h. After cooling to room temperature the mixture was concentrated under vacuum. The residue was dissolved in 20 mL of ethanol. To this solution was added anhydrous hydrazine (1.50 mL, 47.8 mmol), and the mixture was heated at reflux for 2 h. After cooling to room temperature the reaction mixture was concentrated under vacuum, and the residue was dissolved in ethyl acetate. The solution then was washed with aqueous sodium bicarbonate solution and brine, dried over anhydrous sodium sulfate, filtered, and concentrated. Column chromatography on silica gel (elution: 1-5% isopropanol/chloroform w/0.5% conc. ammonia) provided 0.600 g (38%) of tert-butyl 4-(3-(pyridin-2-yl)-1H-pyrazol-4-yl)piperazine-1-carboxylate as an oil; Mass Spec.: m/e: 330.30 (M+H)+ [calc'd: 330.19]; 1H NMR (300 MHz, DMSO-D6) δ 13.19 (br s, 1H), 8.60 (m, 1H), 8.09 (m, 1H), 7.90 (m, 1H), 7.53 (m, 1H), 7.31 (m, 1H), 3.50 (m, 4H), 2.82 (m, 4H), 1.43 (s, 9H).

Workup

  1. temperatureat reflux for 5 h
  2. concentrationwas concentrated under vacuum
  3. dissolutionThe residue was dissolved in 20 mL of ethanol
  4. temperaturethe mixture was heated
  5. temperatureat reflux for 2 h
  6. temperatureAfter cooling to room temperature the reaction mixture
  7. concentrationwas concentrated under vacuum
  8. dissolutionthe residue was dissolved in ethyl acetate
  9. washThe solution then was washed with aqueous sodium bicarbonate solution and brine
  10. dry with materialdried over anhydrous sodium sulfate
  11. filtrationfiltered
  12. concentrationconcentrated

Sources & evidence

ORD record
ord-8809dc88c383409da65bfa003f5309ec
Source dataset
uspto-grants-2010_10
Patent number
US07807676B2

Reaction notes

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