Phosphorus oxychloride → 6-Bromo-1,1,4,4,7-pentamethyl-1,4-dihydronaphthalene

Participants

Reaction Steps

To a solution of 15.3 g (51.5 mmol) of 2-bromo-3-methyl-6-hydroxy-5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalene in 120 ml of pyridine was added 17.9 ml (192 mmol) of phosphorus oxychloride. The reaction mixture was heated to 100°. After 6 h, cooled to room temperature and carefully poured onto ice with stirring. After 1 h, extracted with ethyl acetate, washed with 2 N HCl and brine, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by gravity chromatography (gradient elution: hexane-10% ethyl acetate/hexane) to afford 12.5 g (87%) of 2-bromo-3,5,5,8,8-pentamethyl-5,8-dihydronaphthalene.

Provenance & Evidence