反应详情

A mixture of 5.0 g (28.2 mmol) of 2-bromo-5-methylthiophene, 7.70 g (28.3 mmol) of 4′-ethyl-3-fluoro-4-biphenylboronic acid, 1.70 g (1.47 mmol) of tetrakis(triphenylphosphine)palladium(0) and 30 ml of 2 N sodium carbonate solution in 90 ml of toluene/ethanol (1:2) is refluxed for 3 h. After cooling, the organic phase is separated off, and the aqueous phase is extracted a number of times with toluene. The combined organic phases are washed with water and sat. sodium chloride solution. The solution is dried using sodium sulfate and evaporated to dryness. The residue is purified by column chromatography (SiO2, n-heptane:toluene=97:3). The further purification is carried out by recrystallisation from ethanol and n-heptane, giving 2-(4′-ethyl-3-fluorobiphenyl-4-yl)-5-methylthiophene as a colourless solid (m.p. 102° C.).

1. temperatureis refluxed for 3 h
2. temperatureAfter cooling
3. customthe organic phase is separated off
4. extractionthe aqueous phase is extracted a number of times with toluene
5. washThe combined organic phases are washed with water and sat. sodium chloride solution
6. customThe solution is dried
7. customevaporated to dryness
8. customThe residue is purified by column chromatography (SiO2, n-heptane:toluene=97:3)
9. customThe further purification
10. customis carried out by recrystallisation from ethanol and n-heptane