Ammonium Chloride → 2,2-Dimethyl-4-(5-fluoro-2-methylphenyl)-5-oxopiperazine-1-carboxylic acid t-butyl ester

HRID 1694943Notes

Reaction equation

HRID 1694943 reaction equation
CC(C)([O-])C.[K+].[C:7]([O:11][C:12](=[O:31])[NH:13][C:14]([CH3:30])([CH3:29])[CH2:15][N:16]([C:25](=[O:28])[CH2:26]Br)[C:17]1[CH:22]=[C:21]([F:23])[CH:20]=[CH:19][C:18]=1[CH3:24])([CH3:10])([CH3:9])[CH3:8].[Cl-].[NH4+]>O1CCCC1.O>[C:7]([O:11][C:12]([N:13]1[CH2:26][C:25](=[O:28])[N:16]([C:17]2[CH:22]=[C:21]([F:23])[CH:20]=[CH:19][C:18]=2[CH3:24])[CH2:15][C:14]1([CH3:30])[CH3:29])=[O:31])([CH3:10])([CH3:9])[CH3:8]

Participants

6

Reactant 3

HCID 25517Ammonium ChlorideHCID 23665647Potassium tert-butoxideHCID 66645460{2-[(2-Bromoacetyl)-(5-fluoro-2-methylphenyl)amino]-1,1-dimethylethyl}carbamic acid t-butyl ester

Product 1

HCID 666457692,2-Dimethyl-4-(5-fluoro-2-methylphenyl)-5-oxopiperazine-1-carboxylic acid t-butyl esterYield 78.7%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of 2.87 g of potassium t-butoxide (25.6 mmol) in tetrahydrofuran (170 ml) was added to a solution of 7.13 g of {2-[(2-bromoacetyl)-(5-fluoro-2-methylphenyl)amino]-1,1-dimethylethyl}carbamic acid t-butyl ester obtained in Example (70b) (17.0 mmol) in tetrahydrofuran (170 ml) under a nitrogen atmosphere and under cooling in a dry ice-acetone bath over 20 minutes, and the mixture was stirred at the same temperature for 10 minutes. A saturated ammonium chloride aqueous solution was added to the reaction mixture. The mixture was returned to room temperature and diluted with water, followed by extraction with ethyl acetate. Then, the organic layer was dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (elution solvent:hexane/ethyl acetate=2/1) to obtain 4.5 g of the title compound (yield: 78%).

Workup

  1. temperatureunder cooling in a dry ice-acetone bath over 20 minutes
  2. customwas returned to room temperature
  3. extractionfollowed by extraction with ethyl acetate
  4. dry with materialThen, the organic layer was dried over anhydrous magnesium sulfate
  5. filtrationAfter filtration
  6. customthe solvent was evaporated under reduced pressure
  7. customthe residue was purified by silica gel column chromatography (elution solvent:hexane/ethyl acetate=2/1)

Sources & evidence

ORD record
ord-8afd0522f5f04f5ab096451cad557ff6
Source dataset
uspto-grants-2012_04
Patent number
US08158790B2

Reaction notes

Loading…