Synthesis and Mesomorphic Characteristics of Fluoroaniline Derivatives with Different Lateral Groups

Dave, Jayrang S.; Patel, Purvang D.; Bhatt, Himanshu

doi:10.1080/10426507.2012.669678

Cited by 3 publications

(1 citation statement)

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“…[13][14][15][16][17] Liquid crystal materials bearing azo/ester central linkages and middle and terminal phenyl rings substituted with groups of different polarity as well as nalkoxy group on the other end of the molecule were reported. [18][19][20][21][22][23][24][25][26][27] In previous work [28] in this laboratory, the effect of compact terminal substituent (X), as well as the terminal alkoxy (RO-) group, of varying chain length, on the mesophase behaviour of compounds of the type 4-(4′-substituted phenylazo) phenyl 4″-alkoxybenzoates (IIn af ) was studied. In that work, [28] it was observed that the stability of the mesophase is augmented by an increase in the polarity and/or polarisability of the mesogenic part of the molecule, which is definitely affected by the polarity of the substituent, and its position, which would accordingly affect the polarity of the whole molecular structure by the way the polar substituents electronically interact with the remainder of the molecule.…”

Section: Introductionmentioning

confidence: 99%

Effect of exchange of terminal substituents on the mesophase behaviour of some azo/ester compounds

et al. 2014

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Six homologous series of 4-(4′-alkoxy phenylazo) phenyl 4″-substituted benzoates (In a-f ) were prepared in which, within each homologous series, the length of the terminal alkoxy chain varies between 6, 8, 10, and 12 carbons, while the other terminal substituent, X, is a polar group that alternatively changed from CH 3 O, CH 3 , H, Br, NO 2 and CN. Compounds prepared were characterised by spectroscopic methods, and their mesophase behaviour investigated by differential scanning calorimetry (DSC) and polarised optical microscopy (POM). The results were discussed in terms of mesomeric and polarisability effects. In each group of compounds, bearing the same alkoxy substituent, the nematic-to-isotropic transition temperatures (T C ) were successfully correlated with the polarisability anisotropy of bonds to the substituent X. A comparative study was made between the investigated compounds and their previously prepared isomers, namely, 4-(4′-substituted phenylazo) phenyl 4″-alkoxybenzoates (IIn a-f ) in which the two terminal (alkoxy-and X) groups are exchanged.

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