The synthesis and transition temperatures of some fluorinated terphenyls with alkenyl terminal chains
The synthesis and transition temperatures of some fluorinated terphenyls with alkenyl terminal chains
复制标题
一些带烯基端链的氟化三联苯的合成和转变温度
DOI：
10.1080/00150199608223655
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发表时间：
1996
期刊：
影响因子：
0.8
通讯作者：
K. Toyne
中科院分区：
文献类型：
--
作者：
C. Dong;M. Hird;J. Goodby;P. Styring;K. Toyne
摘要在2，3-或2′，3 ′-二氟三联苯体系的烷氧基端链上引入了碳-碳双键。研究了双键的位置和性质（E/Z）对这些化合物的介晶行为的影响。在所有情况下，近晶C的热稳定性降低。在末端基团的2-位处引入反式双键增加了中间环中具有二氟取代基的化合物的熔点和清亮点;这导致近晶C中间相范围减小，但近晶C中间相范围增大。所有的转变温度降低与顺式双键在3-位。近晶C和近晶C中间相范围均减小，但近晶C范围的减小小于反式-2-烯端基的减小。随着末端环中的二氟取代基连接到烯氧基链，所有的转变温度...
Abstract A carbon-carbon double bond has been introduced into an aliphatic alkoxy terminal chain of 2,3- or 2′,3′- difluoroterphenyl systems. The effect of the position and nature (E/Z) of the double bond on the mesomorphic behaviour of these compounds in comparison with the parent systems has been studied. The smectic C thermal stabilities are reduced in all the cases. The introduction of a trans-double bond at the 2-position of the terminal group increased the melting points and clearing points for the compounds with difluoro substituents in the middle ring; this results in a decrease of the smectic C mesophase range but an increase in the nematic mesophase range. All the transition temperatures are reduced with a cis-double bond at the 3-position. Both smectic C and nematic mesophase ranges are decreased, but the reduction in the smectic C range is less than for the trans-2-ene terminal group. With the difluoro substituents in the end ring linked to the alkenyloxy chain, all the transition temperatures...