摘要
4-烷基取代的反式环己基甲醇是在TFT-LCD中被广泛应用的乙基桥键类液晶的重要中间体,通常是由锂铝氢还原相应的反式环己基羧酸而得。文章尝试以硼氢化钠和路易斯酸组合作为还原剂体系,摸索了路易斯酸的种类及其与硼氢化钠的配比用量和所用溶剂等反应条件。发现在室温下,以乙二醇二甲醚(DME)做溶剂时,AlCl3、ZnCl2以及TiCl4这3个路易斯酸中TiCl4的反应效果最好;通过比较得出反应物与四氯化钛和硼氢化钠之间的最佳摩尔比例为1∶0.73∶2.2。用硼氢化钠和四氯化钛的还原体系在上述反应条件下即可将对位取代的反式环己基羧酸或酯还原为相应的反式环己基甲醇,收率为77%～95%。
4-trans-alkylcyclohexyl methanol is an important intermediate of the liquid crystal containing ethyl-linkage which is widely used in the TFT-LCD.It is usually obtained by the reduction of its corresponding acid using LiAlH4.The reagent sodium borohydride combined with Lewis acid were used as the reduction system in this work.The effects of the ratio of the reduction agent with Lewis acids and solvents were studied.It was found that the reactions involved TiCl4 achieved the best among TiCl4,AlCl3 and ZnCl2 at the room temperature in dimethylethane（DME）.The optimal ratio of reactant with TiCl4 and NaBH4 is 1∶0.73∶2.2（mol）.The reduction of the 4-trans-alkylcyclohexyl carboxylic acid or ester to its corresponding alcohol was successful via the NaBH4＋TiCl4 system under the mild condition.The yields were 77 % - 95 %.
出处
《液晶与显示》
CAS
CSCD
北大核心
2007年第6期652-656,共5页
Chinese Journal of Liquid Crystals and Displays
基金
教育部优秀青年教师资助计划项目
上海市经委人才培养专项资助
