Phenol → HCID 20337459, compound

Participants

Reaction Steps

A solution of 1-bromopropylbenzene (51.7 g., 0.26 mole) in ether (225 ml.) is added dropwise over a one hour period to a refluxing mixture of magnesium (7.32 g.) in ether (78 ml.). The reaction mixture is refluxed for 30 minutes longer and then a solution of 2,5-dimethoxy-acetophenone (50 g.) in ether (60 ml.) is added dropwise and heated to reflux for 1.5 hours. The reaction is quenched by addition of saturated ammonium chloride (250 ml.) the ether layer is separated and the aqueous phase extracted with ether (3×200 ml.). The combined ether extracts are dried over magnesium sulfate and concentrated under vacuum to yield 80.3 g. (100%) of 2-(2'5'-dimethyloxyphenyl)-5-phenyl-2-pentanol as an oil. The oil (78.1 g., 0.26 mole), 21.7 g. of p-toluenesulfonic acid and 1250 ml. of phenol are combined and heated at reflux for one hour, while collecting the water (5.5 ml.) evolved in a Dean-Stark apparatus. The mixture is cooled to room temperature, washed with 200 ml. portions of water, saturated sodium bicarbonate and brine, then dried over magnesium sulfate. The filtered phenol layer yields 75.6 g. of 2-(2',5'-dimethoxyphenyl)-5-phenyl-2-pentene as an orange oil upon evaporation.

Provenance & Evidence