تفاعل #364802

معادلة التفاعل

4′-hydroxy[1,1′]biphenyl-4-carboxylic acid

KOH methanol

potassium carbonate allyl bromide

→

methyl 4′-allyloxy[1,1′]biphenyl-4-carboxylate

المذيبات

methyl ethyl ketone

ظروف التفاعل

الإجراء التجريبي

The methyl ester of commercial 4′-hydroxy[1,1′]biphenyl-4-carboxylic acid (Aldrich, D-89555 Steinheim) was prepared using methanol and sulfuric acid as catalyst, and methyl 4′-allyloxy[1,1′]biphenyl-4-carboxylate (m.p. 149° C.) was prepared therefrom using potassium carbonate/allyl bromide in methyl ethyl ketone as solvent. Conventional hydrolysis of this ester using KOH/methanol gave the free carboxylic acid, which was converted into the acid chloride by the likewise conventional reaction of the acid with thionyl chloride. 9.4 g (34.5 mmol) of this acid chloride and 0.1 g of BHT were dissolved in toluene, and a solution of 5.5 g (34.5 mmol) of 1,4-butanediol monomethacrylate and 4.0 g (39.7 mmol) of triethylamine, dissolved in toluene, was added dropwise at room temperature with stirring. The mixture was then heated at 45° C. for 90 minutes and cooled, the triethylamine hydrochloride was filtered off, and the filtrate was worked up. The crude product was recrystallized from isopropanol, and then had the following phase behavior: crystalline below 68° C., smectic at 68° C., isotropic already below 120° C., decomposes at 120° C.

المصدر