1637480-21-7Relevant articles and documents
Symmetric bent-core liquid crystals of some schiff bases containing azo linkage
Ciobanu, Catalina Ionica,Carlescu, Irina,Lisa, Gabriela,Scutaru, Dan
, p. 7 - 16 (2014/07/07)
The paper presents the synthesis and liquid crystalline properties of some new symmetric bentcore liquid crystals containing a 1,3-dihydroxybenzene central core disubstituted with mesogenic units consisting of three aromatic rings connected through esteric, azomethinic and azo groups. The wings are ended with terminal acyloxy or alkyloxy chains containing 6 to 10 carbon atoms. Compounds were obtained by the condensation reactions between some 4-((4- alcanoyloxyphenyl)azo)benzaldehydes or 4-((4- alkyloxyphenyl)azo)benzaldehydes with the 1,3-phenylene bis(4-aminobenzoate) core. The new synthesized compounds were characterized from structural point of view (1H NMR, 13C NMR, MS spectroscopy) and liquid crystalline properties (polarizing optical microscopy and differential scanning calorimetry). All the banana shaped compounds presented enantiotropic liquid crystalline properties, with a wideranging stability of mesophases both on heating and cooling cycles. The synthesized compounds presented a good thermal stability in the existence range of the mesophases as evidenced by thermogravimetric studies.