反応 #2710

反応方程式

2,2-dimethyl-6-bromo-thiochroman-4-one

Compound M

2,2-dimethyl-6-bromo-thiochroman-4-one

pTSA

4-bromotoluene

t-BuLi

pentane

→

title compound

2,2-Dimethyl-4(tol-4-yl)-6-bromo-thiochrom-3-ene

溶媒

THF

ethylacetate

dichloromethane

THF

反応条件

後処理

1. 1
   workup.ADDITIONThis mixture was added to a flask
2. 2
   workup.STIRRINGand stirred for 16 hours at ambient temperature
3. 3
   その他The reaction was quenched
4. 4
   workup.ADDITIONby adding aq. NH4Cl
5. 5
   抽出the resulting mixture was extracted with ethylacetate
6. 6
   洗浄washed with brine
7. 7
   その他dried
8. 8
   その他the solvent was removed by evaporation
9. 9
   その他The product was isolated by chromatography on silica gel
10. 10
    温度heated to 50° C. for 3 hours
11. 11
    洗浄washed with 10% NaHCO3 (5 mL), brine (5 mL)
12. 12
    乾燥dried with MgSO4
13. 13
    その他the solvent was removed by evaporation

実験手順

To a cold (-78° C.) solution of 4-bromotoluene (720 mg, 4.2 mmol) in THF (8 mL) was added t-BuLi in pentane (1.7M, 0.5 mL, 0.85 mmol). The mixture was warmed to ambient temperature over 30 minutes with stirring. This mixture was added to a flask containing 2,2-dimethyl-6-bromo-thiochroman-4-one (Compound M, 140 mg, 0.4 mmol) and THF (2 mL). and stirred for 16 hours at ambient temperature. The reaction was quenched by adding aq. NH4Cl, and the resulting mixture was extracted with ethylacetate, washed with brine, dried and the solvent was removed by evaporation. The product was isolated by chromatography on silica gel. The material was dissolved in dichloromethane (5 mL) and pTSA (5 mg) was added and heated to 50° C. for 3 hours. The misture was diluted with ethylacetate (20 mL), washed with 10% NaHCO3 (5 mL), brine (5 mL), dried with MgSO4 and the solvent was removed by evaporation to afford the title compound as an off.

出典