反応 #595298

反応方程式

2′,4′-difluoroacetophenone

diethyl 2-chlorobenzylphosphonate

sodium hydride

→

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

収率 26.0%

溶媒

DMF

water

DMF

反応条件

後処理

1. 1
   洗浄freshly washed with dry heptane) in dry DMF (20 ml)
2. 2
   workup.STIRRINGThe resulting mixture was stirred at RT for 68 h
3. 3
   抽出extracted with diethyl ether
4. 4
   その他The organic phase was dried
5. 5
   濃縮concentrated to dryness under reduced pressure
6. 6
   その他the residue was purified by chromatography on silica gel, which

実験手順

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)].

出典