Reaktion #3782

Reaktionsgleichung

potassium tert-butoxide

triphenylphosphine ethyl bromide

2,6-dimethoxy-4-hydroxybenzaldehyde

→

3,5-dimethoxy-4-propylphenol

Ausbeute 55.7%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGfor stirring at room temperature for 30 minutes
2. 2
   workup.STIRRINGfor stirring at room temperature for 2 hours
3. 3
   SonstigeAfter the termination of the reaction
4. 4
   Sonstigethe resulting solution was partitioned with ethyl acetate and dilute hydrochloric acid
5. 5
   Waschenthe resulting ethyl acetate phase was washed in water and subsequently in a saturated sodium chloride solution
6. 6
   Trocknendried over anhydrous magnesium sulfate
7. 7
   workup.DISTILLATIONto distill off the solvents under reduced pressure
8. 8
   SonstigeThe residue was purified by silica gel column chromatography (developing solvent: hexane:ethyl acetate=2:1)
9. 9
   workup.ADDITIONfollowed by addition of a catalytic amount of platinum dioxide for hydrogenation

Vorschrift

Anhydrous tetrahydrofuran (36 ml) was added to triphenylphosphine ethyl bromide (12.3 g) prior to stirring at room temperature for 20 minutes. To the resulting mixture was added potassium tert-butoxide (4.5 g), for stirring at room temperature for 30 minutes. Then, 2,6-dimethoxy-4-hydroxybenzaldehyde (3.0 g) was added to the resulting mixture for stirring at room temperature for 2 hours. After the termination of the reaction, the resulting solution was partitioned with ethyl acetate and dilute hydrochloric acid, and the resulting ethyl acetate phase was washed in water and subsequently in a saturated sodium chloride solution and dried over anhydrous magnesium sulfate, to distill off the solvents under reduced pressure. The residue was purified by silica gel column chromatography (developing solvent: hexane:ethyl acetate=2:1), followed by addition of a catalytic amount of platinum dioxide for hydrogenation, to recover 3,5-dimethoxy-4-propylphenol (1.8 g; yield of 55%). By 1H-NMR (90 MHz, CDCl3), the compound has the peaks shown below.

Quelle