反応 #61517

反応方程式

4-Iodo-5-thiophen-2-yl-2H-pyrazole-3-carboxylic acid ethyl ester

copper cyanide

→

4-Cyano-5-thiophen-2-yl-2H-pyrazole-3-carboxylic acid ethyl ester

溶媒

DMF

反応条件

後処理

1. 1
   その他20 ml of tetrahydrofuran and the solution was degassed with argon
2. 2
   その他The solvent was removed under reduced pressure
3. 3
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
4. 4
   洗浄this solution was washed with saturated aqueous sodium bicarbonate
5. 5
   乾燥The organic phase was dried with sodium sulfate
6. 6
   ろ過filtered
7. 7
   その他the solvent was removed under reduced pressure
8. 8
   その他The product was purified by silica gel chromatography
9. 9
   洗浄eluting with n-heptane

実験手順

1.57 g (4.5 mmol) of 4-Iodo-5-thiophen-2-yl-2H-pyrazole-3-carboxylic acid ethyl ester, 0.81 g (9.0 mmol) of copper cyanide and 352 mg (2.3 mmol) of tetraethylammonium cyanide were dissolved in 10 ml of DMF and 20 ml of tetrahydrofuran and the solution was degassed with argon. 223 mg (0.2 mmol) of Tris(dibenzylideneacetone)dipalladium (0) and 374 mg (0.7 mmol) of 1,1′-bis-(diphenylphosphino) ferrocene were added at RT. The reaction was stirred at 120° C. for 5 h. The solvent was removed under reduced pressure. The residue was dissolved in ethyl acetate and this solution was washed with saturated aqueous sodium bicarbonate. The organic phase was dried with sodium sulfate, filtered and the solvent was removed under reduced pressure. The product was purified by silica gel chromatography eluting with n-heptane:ethyl acetate/1:1.

出典