Reaction #1973900

Reaction equation

compound ( 10 )

8-(4-butoxy-2,3-difluorophenyl)-1,4-dioxaspiro[4.5]decane

formic acid

water

→

1-(4-butoxy-2,3-difluorophenyl)-cyclohexan-4-one

Yield 97.7%

Solvents

toluene

toluene

Conditions

Workup

1. 1
   Temperaturethe mixture was heated
2. 2
   Temperatureto reflux for 2 hours
3. 3
   workup.ADDITIONmixed with it
4. 4
   Otherhad separated into two phases of organic and aqueous phases
5. 5
   Extractionthe extraction into an organic phase
6. 6
   OtherThe resulting organic phase was separated
7. 7
   Washwashed successively with water
8. 8
   Dryinga saturated aqueous solution of sodium hydrogencarbonate and water, and then dried over anhydrous magnesium sulfate
9. 9
   workup.DISTILLATIONThe solvent was then distilled off under reduced pressure
10. 10
    Otherthe resulting residue was purified with a fractional operation by means of column chromatography
11. 11
    OtherThe product was further purified by recrystallization from heptane

Procedure

The compound (10) (47.8 g), formic acid (87%; 67.0 ml) and toluene (200 ml) were mixed, and the mixture was heated to reflux for 2 hours. After the reaction mixture had been cooled to 30° C., water (500 ml) and toluene (1,000 ml) were added to the mixture and mixed with it. The mixture was then allowed to stand until it had separated into two phases of organic and aqueous phases, and the extraction into an organic phase was carried out. The resulting organic phase was separated, and washed successively with water, a saturated aqueous solution of sodium hydrogencarbonate and water, and then dried over anhydrous magnesium sulfate. The solvent was then distilled off under reduced pressure and the resulting residue was purified with a fractional operation by means of column chromatography using silica gel as a stationary phase powder and toluene as an eluent. The product was further purified by recrystallization from heptane to give 1-(4-butoxy-2,3-difluorophenyl)-cyclohexan-4-one (11) (40.4 g). The yield based on the compound (10) was 97.8%.

Source