4,6-Dimethoxysalicylaldehyde → 3,5-Dimethoxy-2-propylphenol

Temperature

50 °C

Triphenylphosphine ethylbromide (4.1 g) was added to 2N sodium hydroxide/dimethyl sulfoxide solution (11 ml), prior to stirring at 50° C. for 30 minutes. To the mixture was added 4,6-dimethoxy-2-hydroxybenzaldehyde (1 g), for stirring at 50° C. overnight. The resulting solution was partitioned between ethyl acetate and dilute hydrochloric acid, and the resulting ethyl acetate phase was washed in water and subsequently in an aqueous 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.

1. stirringfor stirring at 50° C. overnight
2. customThe resulting solution was partitioned between ethyl acetate and dilute hydrochloric acid
3. washthe resulting ethyl acetate phase was washed in water and subsequently in an aqueous saturated sodium chloride solution
4. dry with materialdried over anhydrous magnesium sulfate
5. distillationto distill off the solvents under reduced pressure
6. customThe residue was purified by silica gel column chromatography (developing solvent:hexane:ethyl acetate=3:1)
7. additionfollowed by addition of a catalytic amount of platinum dioxide for hydrogenation

ORD record

ord-fecd372b6c5a4ce294d54a0f4df7017c

Source dataset

uspto-grants-2002_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06495592B1