98459-06-4Relevant academic research and scientific papers
Effects of Polysubstitution on Mesomorphic Properties: Chloro Derivatives of 4-Methoxyphenyl 4-(Phenyliminomethyl)benzoate and Related Compounds
Matsunaga, Y.,Yasuhara, K.
, p. 239 - 249 (2007/10/02)
The effects of mono-, di-, and trichloro substitution of one of the end phenyl rings upon the nematic-isotropic transition temperature have been studied employing seven three-ring systems with a terminal methoxyl group, in which the linkage groups are -CO-O- and -CH=N-.The transition temperatures in these compounds were mostly in this order: 4-Cl > 2,4-Cl2 > 2,3,4-Cl3 > 3,4-Cl2 > unsubstituted > 2,3-Cl2 > 2-Cl or 3-Cl.Both the substituents on the 2- and 3-positions drastically lowered the transition temperature of the parent compound and the extent of depression by the former substituent varied by a factor of more than two when the -CH=N- group nearby was inverted.The condition that the thermal stabilities of mesophases and the temperature ranges over which the mesophases exist must be considerable in a parent compound was not necessarily required for the appearance of an enantiotropic nematic-isotropic transition in laterally substituted derivatives.Keywords: Liquid crystals; nematic; smectic; lateral substituent
Mesogenic Oxaheterocycles and Their Benzene Analogues: Part II
Vora, R. A.,Gupta, Renu,Patel, N. C.
, p. 325 - 326 (2007/10/02)
Two simple homologous series (A, B) of the schiff bases bearing a terminal furyl or phenyl ring have been prepared and the effect of terminal furan ring on mesomorphic properties has been studied.Both the series exhibit only nematic mesophase and usual odd-even effect.The absence of smectic mesophase is somewhat surprising.Behaviour of the two series and their mesophase thermal stabilities have been compared with each other and also with other structurally related series.
