2,3,5-Trimethylphenol → 2-Hydroxy-3,4,6-trimethylbenzaldehyde

A solution of 2,3,5-trimethylphenol (13.6 g, 100 mmol,) in dichloromethane (20 mL) was ice-cooled, titanium tetrachloride (41.7 g, 220 mmol) was added dropwise over 0.5 hr under nitrogen atmosphere, and the reaction mixture was stirred for 1 hr. Dichloromethyl methyl ether (11.5 g, 100 mmol) was added dropwise, and the mixture was further stirred for 6 hr. The reaction mixture was treated with saturated aqueous ammonium chloride solution, and extracted with dichloromethane. The extract was washed successively with diluted hydrochloric acid, saturated aqueous sodium hydrogencarbonate and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=5:95-50:50) to give the title compound (6.58 g, yield 40%) as pale-brown crystals.

1. temperaturecooled
2. stirringthe mixture was further stirred for 6 hr
3. extractionextracted with dichloromethane
4. washThe extract was washed successively with diluted hydrochloric acid, saturated aqueous sodium hydrogencarbonate and saturated brine
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexane=5:95-50:50)

ORD record

ord-20c7c1b696494b6898abbf4ece7eb589

Source dataset

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08492430B2