Water → 4-(1-phenyl-1H-indazol-3-yl)-1-piperazine carboxylic acid ethyl ester

HRID 655009Notes

Reaction equation

HRID 655009 reaction equation
[CH2:1]([O:3][C:4]([N:6]1[CH2:11][CH2:10][N:9]([C:12](=[N:20][NH:21][C:22]2[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=2)[C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=2F)[CH2:8][CH2:7]1)=[O:5])[CH3:2].CC(C)([O-])C.[K+].O>O1CCCC1>[CH2:1]([O:3][C:4]([N:6]1[CH2:11][CH2:10][N:9]([C:12]2[C:13]3[C:18](=[CH:17][CH:16]=[CH:15][CH:14]=3)[N:21]([C:22]3[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=3)[N:20]=2)[CH2:8][CH2:7]1)=[O:5])[CH3:2]

Participants

5

Reactant 3

HCID 962WaterHCID 23665647Potassium tert-butoxideHCID 542902884-[(Phenylhydrazono)(2-fluorophenyl)methyl]-1-piperazine carboxylic acid ethyl ester

Product 1

HCID 151170734-(1-phenyl-1H-indazol-3-yl)-1-piperazine carboxylic acid ethyl esterYield 51%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a stirred solution, under nitrogen of 16.2 g of 4-[(phenylhydrazono)(2-fluorophenyl)methyl]-1-piperazine carboxylic acid ethyl ester in 150 ml of tetrahydrofuran was added, dropwise, a solution of 6.0 g of potassium t-butoxide in 60 ml of tetrahydrofuran. The reaction mixture was stirred at room temperature for 16 hrs., poured into water, and extracted with dichloromethane. The extract was washed with water, dried over anhydrous magnesium sulfate, filtered, and concentrated to an oil. The oil was purified on a Water's Model 500 Preparative High Pressure Liquid Chromatograph utilizing two silica gel columns and hexane/ethyl acetate (3:1 by volume) as the eluent. Concentration of the appropriate fractions yielded 5.3 g (51%) of 4-(1-phenyl-1H-indazol-3-yl)-1-piperazine carboxylic acid ethyl ester.

Workup

  1. extractionextracted with dichloromethane
  2. washThe extract was washed with water
  3. dry with materialdried over anhydrous magnesium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated to an oil
  6. customThe oil was purified on a Water'

Sources & evidence

ORD record
ord-b42455725663436ca12b8f0b7c3040b7
Source dataset
uspto-grants-1992_07
Patent number
US05134236

Reaction notes

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