2-Bromopropane → Ethyl alpha-fluoro-alpha-isopropyl-4-chlorophenylacetate
Reaction equation
[F:1][CH:2]([C:8]1[CH:13]=[CH:12][C:11]([Cl:14])=[CH:10][CH:9]=1)[C:3]([O:5][CH2:6][CH3:7])=[O:4].[CH:15](Br)([CH3:17])[CH3:16].[H-].[Na+].CN(C)P(N(C)C)(N(C)C)=O>C1C=CC=CC=1>[F:1][C:2]([C:8]1[CH:9]=[CH:10][C:11]([Cl:14])=[CH:12][CH:13]=1)([CH:15]([CH3:17])[CH3:16])[C:3]([O:5][CH2:6][CH3:7])=[O:4]Participants
6
Conditions
- Temperature
- 35 °C
Procedure
A mixture of ethyl α-fluoro-4-chlorophenylacetate (2.3 g), isopropyl bromide (1.10 g), sodium hydride (0.56 g of a 50% mixture in oil), dry hexamethylphosphoramide (6 ml) and dry benzene (6 ml) was heated with stirring at a temperature of 35° C. under nitrogen for a period of 22 hours. The reaction mixture was poured into ice-water and the aqueous mixture extracted with methylene chloride. The methylene chloride extract was dried over anhydrous sodium sulfate and solvent removed by distillation under reduced pressure. The product was chromatographed over silica gel using 15% ethylene dichloride in petroleum ether as eluant to give ethyl α-fluoro-α-isopropyl-4-chlorophenylacetate (1.42 g; 62%).
Workup
- temperaturewas heated
- extractionthe aqueous mixture extracted with methylene chloride
- extractionThe methylene chloride extract
- dry with materialwas dried over anhydrous sodium sulfate and solvent
- customremoved by distillation under reduced pressure
- customThe product was chromatographed over silica gel using 15% ethylene dichloride in petroleum ether as eluant
Sources & evidence
- ORD record
- ord-646e20de2fd34f059facbd8be7296bb3
- Source dataset
- uspto-grants-1983_03
- Patent number
- US04376784
Reaction notes
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