反应条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.
实验步骤: A heterogenous solution of acid-washed zinc powder (4.74 g, 72,5 mmol), 3-pentanone (3.84 ml, 36.4 mmol), and dry THF (25 ml) was cooled to 0° C. in an ice-water bath, and a mixture of 3-bromo-3,3-difluoropropene (6.00 g, 38.2 mmol) in dry THF (10 ml) was slowly added. The reaction mixture was allowed to stand at room temperature overnight. Then, aqueous hydrochloric acid (5%, 30 ml) was added to the reaction mixture, which was stirred for 5 minutes. Excess zinc was removed by filtration and washed with ether. The organic phase was washed with saturated sodium bicarbonate solution, water (twice), dried over MgSO4 and concentrated. This oil was dissolved in dichloromethane (50 ml), and triethylamine (7.05 ml, 50.8 mmol) and 4-(N,N-dimethylamino)-pyridine (250 mg) are added. The reaction mixture was cooled to 0° C. and trimethylsilyl chloride (6.42 ml, 50.8 mmol) was added dropwise, and the mixture was stirred at room temperature overnight. The reaction mixture was poured into water and extracted twice with ether. The combined organic layers were washed several times with water, dried over MgSO4, and evaporated in vacuo. The residue was purified by chromatography (50 g silica gel; 2% EtOAc in petroleum ether as eluant) to give the compound as a colourless oil, δ 0.13 (s, 9H), 0.89 (m, 6H), 1.5-1.8 (m, 4H), 5.43 (m, 1H), 5.63 (m, 1H), 5.92-6.13 (m, 1H).
was slowly added
Excess zinc was removed by filtration
washed with ether
The organic phase was washed with saturated sodium bicarbonate solution, water (twice),
dried over MgSO4
concentrated
This oil was dissolved in dichloromethane (50 ml)
the mixture was stirred at room temperature overnight
extracted twice with ether
The combined organic layers were washed several times with water
dried over MgSO4
evaporated in vacuo
The residue was purified by chromatography (50 g silica gel; 2% EtOAc in petroleum ether as eluant)
来源 ID: ord-363aa985c38c4545abfbcf1f6ed6e9a2