Glycerol → 3-(4-Biphenylyl)-2-butenoic acid ethyl ester

Beteiligte Stoffe

Reaktionsschritte

6.45 g (0.1 mole) of activated zinc metal (20 mesh) is placed in a flask fitted with a septum inlet and a magnetic stirrer. The system is maintained under a nitrogen atmosphere and kept at a temperature of 25° C. on a water bath. A solution of 19.6 g (0.1 mole) of 4-acetylbiphenyl in 75 ml of dry tetrahydrofuran and 75 ml of trimethyl borate (distilled from calcium hydride) is injected and the mixture stirred. 11.1 ml (0.1 mole) of freshly distilled ethyl bromoacetate is injected in one shot and the mixture stirred at 25° C. for 12 hours. A mixture of 25 ml of concentrated ammonium hydroxide and 75 ml of glycerine is added, and the aqueous phase is separated and extracted thrice with 25 ml portions of diethyl ether. The combined organic extracts are dried over anhydrous magnesium sulphate and the diethylether removed on a rotary evaporator, the residue is vacuum distilled and the fraction distilling at 0.125 mn at 171°-172° C. is collected. Recrystallisation from petroleum ether yields the heading compound, substantially in trans form.

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