Реакция #2700

Уравнение реакции

4-bromotoluene

3,4-dihydro-4,4-dimethyl-7-bromo-1(2H)-naphthalenone

Compound A

3,4-dihydro-4,4-dimethyl-7-bromo-1(2H)-naphthalenone

→

title compound

1-(Tol-4-yl)3,4-dihydro-4,4-dimethyl-7-bromo-naphthalene

Растворители

THF

THF

THF

ethylacetate

THF

Условия реакции

Обработка

1. 1
   Температураheated to 70° C. for 30 minutes
2. 2
   ТемператураAfter cooling to ambient temperature
3. 3
   Температураheated to 70° C. for 24 hours
4. 4
   ТемператураThe mixture was cooled to ambient temperature
5. 5
   Другоеthe reaction was quenched by addition of H2O
6. 6
   workup.ADDITIONThe mixture was diluted with ether:ethylacetate (1:1, 100 mL)
7. 7
   Промывкаwashed with saturated NH4Cl (15 mL), water (10 mL) and brine (10 mL)
8. 8
   СушкаThe organic layer was dried with MgSO4
9. 9
   ДругоеSolvent was removed under reduced pressure
10. 10
    Другоеto afford the crude product as an off
11. 11
    Температураthe mixture was refluxed for 16 hours
12. 12
    ТемператураThe mixture was cooled to ambient temperature
13. 13
    Промывкаwashed with 10% NaHCO3 (20 mL), brine (20 mL)
14. 14
    Сушкаdried with MgSO4
15. 15
    Другоеthe solvent wasremoved by evaporation
16. 16
    ДругоеPurification by chromatography on silica gel

Методика

To a mixture of Mg metal (650 mg, 27 mmol) in THF (20 mL) was added 4-bromotoluene (5.3 g, 31 mmol) in THF (40 mL). The mixture was stirred for 2 hours at ambient temperature and heated to 70° C. for 30 minutes. After cooling to ambient temperature, 3,4-dihydro-4,4-dimethyl-7-bromo-1(2H)-naphthalenone (Compound A) (2.1 g, 8 mmol), in THF (5 mL) was added and heated to 70° C. for 24 hours. The mixture was cooled to ambient temperature and the reaction was quenched by addition of H2O. The mixture was diluted with ether:ethylacetate (1:1, 100 mL) and washed with saturated NH4Cl (15 mL), water (10 mL) and brine (10 mL). The organic layer was dried with MgSO4. Solvent was removed under reduced pressure to afford the crude product as an off. The product was dissolved in THF (20 mL). To this solution p-toleune sulfonic acid (pTSA) (35 mg) was added and the mixture was refluxed for 16 hours. The mixture was cooled to ambient temperature, diluted with ethylacetate (160 mL), washed with 10% NaHCO3 (20 mL), brine (20 mL), dried with MgSO4 and the solvent wasremoved by evaporation. Purification by chromatography on silica gel gave the title compound as a white solid.

Источник