Sulfuric Acid → HCID 57825044, compound

Participants

Reaction Steps

Concentrated sulfuric acid (1.5 mL) was added cautiously to a stirred solution of 1-(3-bromo-4-chlorophenyl)-1-(4-methoxy-3-methylphenyl)-ethanol (6.7 g, 0.019 mol) in methanol (200 mL). The reaction mixture was stirred at reflux for 90 minutes then concentrated to remove methanol. The residue was partitioned between hexane (100 mL) and water (150 mL) and the layers separated. The aqueous fraction was extracted with hexane (2×75 mL) and the combined organic extracts were washed with brine (75 mL), dried (sodium sulfate) and concentrated to give the crude product as a yellow oil, which was purified by dry flash chromatography (0 to 1% ethyl acetate/hexane) to give the alkene as a slowly crystallising colourless oil (4.5 g, 70%), mp 79-81° C. 1H NMR (300 MHz; CDCl3) 7.61 (1H, d, J 2.1, Ar), 7.39 (1H, d J 8.3, Ar), 7.21 (1H, dd J 8.3 & 2.1, Ar), 7.09-7.06 (2H, m, Ar), 6.79 (1H, d, J 8.3, Ar), 5.41 (1H, s, olefinic), 5.33 (1H, s, olefinic), 3.85 (3H, s, OMe), 2.21 (3H, s, Me).

Provenance & Evidence