Reaction #3781

Reaction equation

Triphenylphosphine ethylbromide

sodium hydride dimethyl sulfoxide

4,6-dimethoxy-2-hydroxybenzaldehyde

→

3,5-dimethoxy-2-propylphenol

Yield 46.4%

Conditions

Workup

1. 1
   Otherat 50° C.
2. 2
   Otherovernight
3. 3
   OtherAfter the termination of the reaction
4. 4
   Otherthe resulting solution was partitioned with ethyl acetate and dilute hydrochloric acid
5. 5
   Washthe resulting ethyl acetate phase was washed in water and subsequently in a saturated sodium chloride solution
6. 6
   Dryingdried over anhydrous magnesium sulfate
7. 7
   workup.DISTILLATIONto distill off the solvents under reduced pressure
8. 8
   OtherThe residue was purified by silica gel column chromatography (developing solvent: hexane:ethyl acetate=3:1)
9. 9
   workup.ADDITIONfollowed by addition of a catalytic amount of platinum dioxide for hydrogenation

Procedure

Triphenylphosphine ethylbromide (4.1 g) was added to a 2N sodium hydride/dimethyl sulfoxide solution (11 ml), prior to agitation at 50° C. for 30 minutes. To the mixture was added 4,6-dimethoxy-2-hydroxybenzaldehyde (1 g), for agitation at 50° C. overnight. 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=3:1), followed by addition of a catalytic amount of platinum dioxide for hydrogenation, to recover 3,5-dimethoxy-2-propylphenol (0.5 g; yield of 46%). By 1H-NMR (90 MHz, CDCl3), the compound has the peaks shown below.

Source