Oxalyl chloride → 1-(4-Methylphenyl)cyclopentane carboxylic acid t butyl ester
Reaction equation
[CH3:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2([C:13]([OH:15])=[O:14])[CH2:12][CH2:11][CH2:10][CH2:9]2)=[CH:4][CH:3]=1.C(Cl)(=O)C(Cl)=O.[CH3:22][C:23]([CH3:26])([O-])[CH3:24].[K+]>ClCCl.CN(C=O)C.C1COCC1>[C:23]([O:14][C:13]([C:8]1([C:5]2[CH:4]=[CH:3][C:2]([CH3:1])=[CH:7][CH:6]=2)[CH2:12][CH2:11][CH2:10][CH2:9]1)=[O:15])([CH3:26])([CH3:24])[CH3:22]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 0 °C
Procedure
To a suspension of 1-(4-methylphenyl)cyclopentane carboxylic acid (3.00 g, 14.7 mmol) in dichloromethane (50 mL) at 0° C. was added oxalyl chloride (1.54 mL, 17.4 mmol) and DMF (2 drops). The mixture was stirred at 0° C. for 1 hour, and at rt for 2 hours. The solution was concentrated, diluted with THF (40 mL), and cooled to 0° C. Potassium t butoxide (1.80 g, 16.2 mmol) in THF (20 mL) was slowly added, and the mixture was stirred overnight at rt. Additional potassium t butoxide (0.660 g, 5.88 mmol) was added. After 20 minutes the solution was concentrated to dryness, and taken up in ethyl acetate. The organic phase was washed with 10% citric acid, saturated NaHCO3 and brine, dried (MgSO4), and concentrated. Flash column chromatography (10% ethyl acetate/hexane) gave 1-(4-methylphenyl)cyclopentane carboxylic acid t butyl ester (3.27 g, 87%).
Workup
- waitat rt for 2 hours
- concentrationThe solution was concentrated
- additiondiluted with THF (40 mL)
- temperaturecooled to 0° C
- stirringthe mixture was stirred overnight at rt
- concentrationAfter 20 minutes the solution was concentrated to dryness
- washThe organic phase was washed with 10% citric acid, saturated NaHCO3 and brine
- dry with materialdried (MgSO4)
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-a59c9360ed314472892521833e0452a2
- Source dataset
- uspto-grants-2000_04
- Patent number
- US06054470
Reaction notes
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