Reacción #83600

Ecuación de reacción

methyl 4-(2-t-butyldimethylsiloxyethyl)cinnamate

ethanol

→

1-(2-t-butyldimethylsiloxyethyl)-4-(2-methoxycarbonylpropyl)benzene

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe catalyst was removed by filtration
2. 2
   Concentraciónthe filtrate was concentrated under reduced pressure
3. 3
   workup.ADDITIONTo a solution of the residue in tetrahydrofuran (35 ml) was added lithium bis(trimethylsilyl)amide (1.0 mol/l solution in tetrahydrofuran, 3.9 ml) at -78° C.
4. 4
   workup.STIRRINGthe mixture was stirred at the same temperature for 30 minutes
5. 5
   workup.ADDITIONTo the reaction mixture was added a solution of iodomethane (0.533 g) in tetrahydrofuran (2 ml)
6. 6
   workup.STIRRINGthe mixture was stirred at room temperature for 1 hour
7. 7
   workup.ADDITIONTo the reaction mixture was added water
8. 8
   Extracciónthe mixture was extracted with diethyl ether
9. 9
   LavadoThe extract was washed with water
10. 10
    Secadodried over anhydrous MgSO4
11. 11
    OtroThe solvent was removed under reduced pressure
12. 12
    Otrothe residue was purified by medium pressure liquid column chromatography on a silica gel column
13. 13
    workup.ADDITIONa mixture of n-hexane and methylene chloride (3:1) as eluent

Procedimiento

To a solution of methyl 4-(2-t-butyldimethylsiloxyethyl)cinnamate (1.53 g) in ethanol (25 ml) was added a 10% palladium on activated carbon (0.15 g), and the mixture was stirred at room temperature for 2 hours under an atmosphere of hydrogen. The catalyst was removed by filtration, and the filtrate was concentrated under reduced pressure. To a solution of the residue in tetrahydrofuran (35 ml) was added lithium bis(trimethylsilyl)amide (1.0 mol/l solution in tetrahydrofuran, 3.9 ml) at -78° C., and the mixture was stirred at the same temperature for 30 minutes. To the reaction mixture was added a solution of iodomethane (0.533 g) in tetrahydrofuran (2 ml), and the mixture was stirred at room temperature for 1 hour. To the reaction mixture was added water, and the mixture was extracted with diethyl ether. The extract was washed with water, and dried over anhydrous MgSO4. The solvent was removed under reduced pressure, and the residue was purified by medium pressure liquid column chromatography on a silica gel column using a mixture of n-hexane and methylene chloride (3:1) as eluent to give 1-(2-t-butyldimethylsiloxyethyl)-4-(2-methoxycarbonylpropyl)benzene (0.724 g) as a colorless oily liquid.

Fuente