反应详情

1.60 g (21.98 mmol) of n-butyllithium (2.5N in n-hexane) are added dropwise to 4.44 g (27.41 mmol) of 2-(4-fluorophenyl)furan in 40 ml of absolute tetrahydrofuran at -75° C. After stirring for 45 min, 5.21 g (42.86 mmol) of 2-chloro-N,N-dimethylacetamide in 20 ml of absolute tetrahydrofuran are added at -75° C. After 60 min, the mixture is poured into 200 ml of ice-water, neutralized at 0° C. with 2N hydrochloric acid and extracted 6× with 60 ml of ethyl acetate each time, the combined organic phases are washed 2× with 20 ml of water each time, dried over sodium sulphate and filtered, and the solvent is stripped off. The product is purified by column chromatography (280 g of silica gel 60; solvent: PE/EA 20:1), recrystallized from ethanol and digested with diisopropyl ether.

1. waitAfter 60 min
2. extractionextracted 6× with 60 ml of ethyl acetate each time
3. washthe combined organic phases are washed 2× with 20 ml of water each time
4. dry with materialdried over sodium sulphate
5. filtrationfiltered
6. customThe product is purified by column chromatography (280 g of silica gel 60; solvent: PE/EA 20:1)
7. customrecrystallized from ethanol