Reacción #2045102

Ecuación de reacción

(E)-3-(4-Ethylphenyl)-2-methyl-2-propen-1-ol

acetic anhydride

pyridine

→

product

(E)-3-(4-Ethylphenyl)-2-methyl-2-propenyl Acetate

Disolventes

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe dichloromethane was removed on a rotary evaporator
2. 2
   workup.DISSOLUTIONthe residue dissolved in EtOAc
3. 3
   LavadoThis solution was washed with aqueous 10% HCl, aqueous 10% NaOH, and saturated aqueous NaCl
4. 4
   SecadoThe organic phase was dried (MgSO4)
5. 5
   Filtraciónfiltered
6. 6
   Concentraciónconcentrated
7. 7
   OtroThe product was purified by silica gel flash chromatography (hexane/EtOAc=80:20)
8. 8
   workup.DISTILLATIONfollowed by Kugelrohr distillation (140-160° C., 0.05 mbar)

Procedimiento

(E)-3-(4-Ethylphenyl)-2-methyl-2-propen-1-ol (4.6 g, 26 1 mmol, obtained by LiAlH4 reduction of (E)-3-(4-ethylphenyl)-2-methyl-2-propenal as described for (E)-2-Ethyl-3-(4-methylphenyl)-2-propen-1-ol) was added to a mixture of acetic anhydride (4.0 g, 39 mmol), pyridine (3.5 g, 44 mmol) and DMAP (0.46 g, 3.7 mmol) in 50 ml of dichloromethane. The mixture was stirred for 20 hours at room temperature. The dichloromethane was removed on a rotary evaporator, and the residue dissolved in EtOAc. This solution was washed with aqueous 10% HCl, aqueous 10% NaOH, and saturated aqueous NaCl. The organic phase was dried (MgSO4), filtered and concentrated. The product was purified by silica gel flash chromatography (hexane/EtOAc=80:20) followed by Kugelrohr distillation (140-160° C., 0.05 mbar) yielding 3.9 g (17.9 mmol, 69% yield) of the product as a colorless oil.

Fuente