摘要
Abstract
2[4′[difluoro (3,4,5trifluoro2methylphenoxy)methyl]-3′,5′difluoro [1,1′biphenyl]-4yl]-5alkyltetrahydropyran derivatives was synthesized via butyl lithium,dehydroxylation,Suzuki and Williamson reaction (five steps'reaction)by employing 1,4-Dibromo-benzene,5-alkyl-tetrahydro-py-ran-2-one and 3,4,5-Trifluoro-2-methyl-phenol as starting materials.The effects of reaction tempera-ture,solvent,catalyst and material ratio on the yield were investigated.The optimum reaction condi-tions for the Dehydroxylation reaction,the mole ratio of hydroxyl compounds,triethylsilane and boron trifluoride diethyl ether is 1 :1.5 :2.5 under the drop-temperature at -70 ~-80 ℃.For the Suzuki reaction,(beta-4)-platinum was the best catalysts.The optimum reaction condition for Wil-liamson etherification of 3,4,5-Trifluoro-2-methyl-phenol were 6 h in DMSO-water mixed solvent. After purification processing,the total yield was 35.6% with the purity was 99.5% (GC),the struc-ture was characterized by 1 H NMR and GC-MS.The addition of the compound into the basic formula of liquid crystal,could improve the dielectric anisotropy (Δε),and could reduce threshold voltage as well.关键词
四氢吡喃/3,4,5-三氟-2-甲基苯酚/电光性能/液晶化合物Key words
tetrahydropyran/3/4/5-Trifluoro-2-methyl-phenol/electro-optical property/liquid crystal compound分类
数理科学
