Ethyl isobutyrate → ethyl 4-chloro-2,2-dimethylbutyrate

Temperature

-78 °C

To a solution of 22.2 ml of diisopropylamine in 150 ml of tetrahydrofuran being stirred, 93.6 ml of a 1.6 M solution of n-butyl lithium in hexane was added at -5° to 0° C., followed by stirring for 30 minutes. After the reaction mixture was cooled to -78° C. and 19.0 ml of ethyl isobutyrate was added dropwise to the mixture and stirred for 45 minutes. A solution of 11.9 ml of 1-bromo-2-chloroethane in 10 ml of tetrahydrofuran was added dropwise to the reaction mixture. After the reaction mixture was stirred at -78° C. for 1 hour and then at roomtemperature (15° to 20° C.) for 2 hours, an excess amount of an aqueous solution of ammonium chloride was added, followed by extractionwith ethyl acetate. After the extract was washed with water and dried over MgSO4, the solvent was distilled off; the residue was then distilled under reduced pressure, to yield 24.7 g of the title compound in the form of a colorless oily substance.

1. stirringstirred for 45 minutes
2. stirringAfter the reaction mixture was stirred at -78° C. for 1 hour
3. waitat roomtemperature (15° to 20° C.) for 2 hours
4. extractionfollowed by extractionwith ethyl acetate
5. washAfter the extract was washed with water
6. dry with materialdried over MgSO4
7. distillationthe solvent was distilled off
8. distillationthe residue was then distilled under reduced pressure

ORD record

ord-6788a144a8f145d0899ed1b1e9de313d

Source dataset

uspto-grants-1996_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05491145