Phenylglyoxal → 4'-n-Octylbenzoin

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Reaction Conditions

Reaction Steps

57.0 g (0.30 mole) of n-octylbenzene are dissolved in 800 ml of carbon disulfide, the solution is cooled to 0° C., 66.5 g (0.50 mole) of aluminum chloride are added, and a solution of 40.0 g (0.30 mole) of phenylglyoxal and 50 ml of carbon disulfide are added dropwise at from 5° to 10° C., while stirring vigorously. The yellow to orange reaction mixture is stirred for a further 15 hours without being cooled, after which it is poured carefully onto 1 l of semiconcentrated ice-cold hydrochloric acid, and the mixture is stirred thoroughly. The phases are separated, the organic phase is extracted by shaking with 300 ml of water, the aqueous phases are extracted with 300 ml of methylene chloride, and the combined organic phases are dried over sodium sulfate. The solution is filtered and the solvent is distilled off to give 75.0 g (=77% of theory) of crude product which has a melting range of 85°-89° C. and is 95% pure according to gas chromatography. Recrystallization from methanol gives analytically pure 4'-n-octylbenzoin.

Provenance & Evidence