Ozone → 2-Bromo-4-chloro-6-(2-hydroxyethyl)phenol

Participants

Reaction Steps

A solution of 2-allyl-6-bromo-4-chlorophenol (1.378 g, 5.567 mmol) in 20 mL dichloromethane was cooled at −78° C. While stirring at this temperature, ozone was bubbled through the reaction solution for 6.5 hours. After flushing the reaction vessel with oxygen, while still at −78° C., the reaction was quenched with sodium tetrahydroborate (1.064 g, 28.12 mmol). The reaction was then warmed to room temperature and stirred overnight. The reaction mixture was partitioned between ethyl acetate and water, and the organic layer washed with brine, dried over magnesium sulfate, and evaporated in vacuo. The crude product was purified via flash chromatography on silica gel (10 to 60% ethyl acetate in heptanes) to yield 0.5911 g (42%) of 2-bromo-4-chloro-6-(2-hydroxyethyl)phenol. 1H NMR (400 MHz, CDCl3) δ: 7.38 (d, J=2.5, 1H), 7.27 (s, 1H), 7.06 (d, J=2.4, 1H), 3.96 (br s, 2H), 2.91 (t, J=5.7, 2H), 1.98 (s, 1H).

Provenance & Evidence