Реакция #53289

Уравнение реакции

tert-Butyl bromoacetate

2,6-Difluoroacetophenone

lithium bis(trimethylsilyl)amide

→

title compound

tert-Butyl 4-(2,6-difluorophenyl)-4-oxobutyrate

Растворители

EtOAc

THF

DMPU

Условия реакции

Обработка

1. 1
   workup.STIRRINGThe reaction mixture was stirred for an additional 10 minutes
2. 2
   Температураwarmed to room temperature for 4 hours
3. 3
   Промывкаwashed with water and brine
4. 4
   ЭкстракцияThe aqueous layer was extracted one more time with EtOAc
5. 5
   СушкаThe combined organic layers were dried over Na2SO4
6. 6
   Фильтрацияfiltered
7. 7
   Концентрированиеconcentrated
8. 8
   Другоеpurified by flash chromatography on a silica gel column (hex:ethyl acetate, 2:1)

Методика

To a stirred solution of 2,6-Difluoroacetophenone (5 g, 32 mmol) in dry THF (40 ml) and DMPU (8 ml) was added a solution of lithium bis(trimethylsilyl)amide (1.0M, 45 ml) at −60° C. under argon. After stirring for 10 minutes at −60° C., tert-Butyl bromoacetate (6.99 g, 35.8 mmol) was added rapidly. The reaction mixture was stirred for an additional 10 minutes and then warmed to room temperature for 4 hours. The crude mixture was taken in EtOAc and washed with water and brine. The aqueous layer was extracted one more time with EtOAc. The combined organic layers were dried over Na2SO4, filtered, concentrated and purified by flash chromatography on a silica gel column (hex:ethyl acetate, 2:1) to provide the title compound.

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