反应详情

9.3 g of sodium nitrite dissolved in the minimum amount of water was added to a mixture of 18.18 g of p-amino-acetophenone, 36 ml of concentrated hydrochloric acid and 36 g of water, and the resulting mixture was ice-cooled and diazotized while stirring. To the diazotized solution was added 127 cc of a solution of 16.9 g of β-2-thienylacrylic acid in acetone. An aqueous solution of 25.4 g of sodium acetate dissolved in 10 ml of water and 5.6 g of cupric chloride were then added to the mixture whereby a gas evolved and the reaction proceeded. After the reaction mixture was stirred for 24 hours while cooling, the acetone was distilled off and the residue was extracted with benzene. The benzene layer was shaken with a 5% aqueous sodium hydroxide solution, washed with water and dried over Na2SO4. The drying agent used was filtered out and the solvent was distilled off. The resulting residue was purified by column chromatography on alumina using benzene as a developing solvent to obtain 13.73 g of (E)-2-(4-acetylstyryl)thiophene in a 50% yield. The melting point of the product after recrystallization from benzene was 130° to 131° C.

1. temperaturecooled
2. stirringAfter the reaction mixture was stirred for 24 hours
3. temperaturewhile cooling
4. distillationthe acetone was distilled off
5. extractionthe residue was extracted with benzene
6. stirringThe benzene layer was shaken with a 5% aqueous sodium hydroxide solution
7. washwashed with water
8. dry with materialdried over Na2SO4
9. filtrationThe drying agent used was filtered out
10. distillationthe solvent was distilled off
11. customThe resulting residue was purified by column chromatography on alumina