反応 #411435

反応方程式

ethyl 4-(2,2-dimethyl-4-trifluoromethanesulfonyloxy-(2H)-thiochromen-6-ylethynyl)-benzoate

tert-butyllithium

4-ethylbromobenzene

→

Ethyl 4-[[4-(4-ethylphenyl)-2,2-dimethyl-(2H)-thiochromen-6-yl]-ethynyl]-benzoate

溶媒

THF

THF

pentane

THF

反応条件

後処理

1. 1
   その他to give a yellow solution
2. 2
   温度This solution was heated to 50° C. for 1 h
3. 3
   温度cooled to room temperature
4. 4
   その他the reaction quenched by the addition of saturated aqueous NH4Cl
5. 5
   抽出This solution was extracted with EtOAc
6. 6
   洗浄the combined organic layers washed with H2O and saturated aqueous NaCl
7. 7
   乾燥before being dried (MgSO4)
8. 8
   濃縮concentrated under reduced pressure

実験手順

A solution of 4-ethylbromobenzene (670.9 mg. 3.63 mmol) in 4.0 mL of THF was cooled to −78° C. and tert-butyllithium (464.5 mg. 7.25 mmol, 4.26 mL of a 1.7M solution in pentane) was added to give a yellow solution. After 30 min a solution of ZnCl2 (658.7 mg. 4.83 mmol) in 8.0 mL THF was slowly added via cannula. The resulting solution was warmed to room temperature and transferred via cannula to a solution of ethyl 4-(2,2-dimethyl-4-trifluoromethanesulfonyloxy-(2H)-thiochromen-6-ylethynyl)-benzoate (1.20 g. 2.42 mmol) and tetrakis (triphenylphosphine) palladium(0) (111.7 mg. 0.097 mmol) in 8.0 mL THF. This solution was heated to 50° C. for 1 h, cooled to room temperature, and the reaction quenched by the addition of saturated aqueous NH4Cl. This solution was extracted with EtOAc and the combined organic layers washed with H2O and saturated aqueous NaCl before being dried (MgSO4) and concentrated under reduced pressure. Ethyl 4-[[4-(4-ethylphenyl)-2,2-dimethyl-(2H)-thiochromen-6-yl]-ethynyl]-benzoate was isolated by column chromatography (5% EtOAc/hexanes) as a colorless oil. 1H NMR (300 MHz, CDCl3): δ7.99 (2h, D, j=8.2 Hz), 7.52 (2H, d, J=8.4 Hz), 7.40 (5H, m), 7.35 (2H, m), 5.85 (1H, s), 4.38 (2H, q, J=7.1 Hz), 2.72 (2H, q, J=7.6 Hz), 1.48 (6H, s), 1.40 (3H, t, J=7.1 Hz), 1.30 (3H, t, J=7.6 Hz).

出典