Reacción #1477

Ecuación de reacción

t-butyl magnesium chloride

MeOH

p-tolylsulfonic acid

7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one

Compound G

7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one

→

title compound

7-Bromo-1-(1,1-dimethylethyl)-3,4-dihydro-4,4-dimethylnaphthalene

Disolventes

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe reaction was quenched at 0° C. with saturated ammonium chloride solution (20 ml)
2. 2
   Extracciónextracted with EtOAc (2×50 ml)
3. 3
   ExtracciónThe combined extract
4. 4
   Lavadowas washed with water (20 ml), brine (20 ml)
5. 5
   Secadodried over MgSO4
6. 6
   OtroThe solvent was evaporated under reduced pressure
7. 7
   Otroto afford a yellow oil
8. 8
   OtroThe resultant reaction solution
9. 9
   Temperaturawas heated in an oil bath (60° C.) for 3 h
10. 10
    TemperaturaThe reaction was cooled
11. 11
    Otroquenched with water (20 ml)
12. 12
    Extracciónextracted with EtOAc (2×50 ml)
13. 13
    ExtracciónThe combined extract
14. 14
    Lavadowas washed with saturated NaHCO3 (20 ml), water (20 ml), brine (20 ml)
15. 15
    Secadodried over MgSO4
16. 16
    ConcentraciónThe solvent was concentrated in vacuo

Procedimiento

In a flame dried round bottom flask 7-bromo-3,4-dihydro-4,4-dimethylnaphthalen-1(2H)-one (Compound G, 2.0 g, 7.93 mmol) was dissolved in anhydrous THF (50 ml) and 3,4,5,6,-tetrahydro-2(H)-pyrimidinone (DMPU) (11.5 ml, 95.16 mmol) was added, under argon atmosphere. The reaction was then cooled to -20° C. and a solution of t-butyl magnesium chloride (16 ml, 31.7 mmol) (2M in Et2O) was added dropwise and stirred at -20° C. for 2 h and at ambient temperature for 1 h, under argon atmosphere. The reaction was quenched at 0° C. with saturated ammonium chloride solution (20 ml) and extracted with EtOAc (2×50 ml). The combined extract was washed with water (20 ml), brine (20 ml) and dried over MgSO4. The solvent was evaporated under reduced pressure to afford a yellow oil. To this yellow oil were added MeOH (50 ml) and p-tolylsulfonic acid (100 mg). The resultant reaction solution was heated in an oil bath (60° C.) for 3 h. The reaction was cooled and quenched with water (20 ml), extracted with EtOAc (2×50 ml). The combined extract was washed with saturated NaHCO3 (20 ml), water (20 ml), brine (20 ml), and dried over MgSO4. The solvent was concentrated in vacuo and the title compound was obtained as a colorless oil after purification by flash chromatography (silica, hexane).

Fuente