Реакция #595298

Уравнение реакции

2′,4′-difluoroacetophenone

diethyl 2-chlorobenzylphosphonate

sodium hydride

→

1-[1-(2-chlorophenyl)prop-1-en-2-yl]-2,4-difluorobenzene

Выход 26.0%

Растворители

DMF

water

DMF

Условия реакции

Обработка

1. 1
   Промывкаfreshly washed with dry heptane) in dry DMF (20 ml)
2. 2
   workup.STIRRINGThe resulting mixture was stirred at RT for 68 h
3. 3
   Экстракцияextracted with diethyl ether
4. 4
   ДругоеThe organic phase was dried
5. 5
   Концентрированиеconcentrated to dryness under reduced pressure
6. 6
   Другоеthe residue was purified by chromatography on silica gel, which

Методика

At 3° C., a solution of diethyl 2-chlorobenzylphosphonate (2.00 g, 7.61 mmol) in dry DMF (30 ml) was added to a stirred suspension of sodium hydride (60% by weight suspension in mineral oil, 365 mg, 9.13 mmol; freshly washed with dry heptane) in dry DMF (20 ml). After 1 h of stirring at 3° C., a solution of 2′,4′-difluoroacetophenone (1.31 g, 8.37 mmol) in dry DMF (20 ml) was added dropwise. The resulting mixture was stirred at RT for 68 h and then diluted with water and extracted with diethyl ether. The organic phase was dried and concentrated to dryness under reduced pressure, and the residue was purified by chromatography on silica gel, which gave 1-[1-(2-chlorophenyl)prop-1-en-2-yl]-2,4-difluorobenzene as a 93/7 mixture of diastereoisomers [colourless solid, 560 mg, yield 26%; GC/MS: m/z=264 (M+); HPLC/MS: log P(HCOOH)=5.05 (major diastereoisomer), 5.34 (minor diastereoisomer)].

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