末端为二氟乙烯氧基类液晶分子的合成

报道了末端基团为二氟乙烯氧基、具有苯基双环己烷骨架的液晶化合物的合成方法。3,5-二氟溴苯的格氏试剂与烷基双环己基酮偶联,经过脱水、氢化、异构化、类Brown硼氢化、醚化,最后经过消除反应得到5-反-4′-(反-4″-正丙基环己基)环己基]-1,3-二氟-2-(2′,2′-二氟乙烯氧基)苯,该法原料易得、实验步骤少,总收率15%,其结构经1HNMR确证。

Synthesis of terminal difluoroethyleneoxy group liquid crystal

A method for synthesis of liquid crystals with a terminal difluoroethyleneoxy group and a backbone of phenylbicyclohexane was reported in detail.5-trans-4′-(4″-trans-n-Propylcyclohexyl)cyclohexyl]-1,3-difluoro-2-(2′,2′-difluoroethyleneoxy)benzene was obtained by coupling of 4-alkylcyclohexylcyclohexanone with the Grignard reagent of 3,5-difluorobromobenzene,followed by dehydration,hydrogenation,isomerization,Brown borohydride,Williamson reaction and elimination reactions.The overall yield was greater than 15%.This process has many advantages,including cheap starting materials,fewer experimental steps,and the product structure was confirmed by 1HNMR spectroscopy.