Chloroform → 4-Hydroxy-(1,1'-biphenyl)-3-carbaldehyde

Beteiligte Stoffe

Reaktionsschritte

22 g of p-phenylphenol was dissolved in 95% ethanol; a solution of 40 g of sodium hydroxide in 80 ml of water was rapidly added. The resulting solution was heated to 75°-80° C. and 20 ml of chloroform was added over a one-hour period, the mixture being gently refluxed. The mixture then was stirred for three hours, cooled and the ethanol and excess chloroform were evaporated under reduced pressure. The resulting residue was cooled and poured into cold water. The resulting mixture was acidified by slow addition of hydrochloric acid and extracted with ether. The solvent was evaporated from the extract under reduced pressure, the residue was poured in twice its volume of saturated sodium metabisulfite solution and the mixture was shaken vigorously for forty-five minutes. The resulting semisolid bisulfite addition compound was allowed to stand for one hour, filtered in the dark and washed with small portions of ethanol and ether to remove the phenol. The bisulfite addition compound was decomposed with dilute sulfuric acid, the mixture being warmed on a water-bath for thirty minutes. The cooled mixture was extracted with ether. The extract was dried (Na2SO4), and the solvent was evaporated under reduced pressure. The residue was treated with activated charcoal and recrystallized from ethanol/water to give 5-phenylsalicylaldehyde (5A) as yellow crystals, mp: 98°-99° C.

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