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Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
Synthesis and liquid crystalline properties of new diols containing azomethine groups
Issam Ahmed Mohammed1, Govindarajan Sankar, Melati Khairuddean
1School of Industrial Technology, University Sains Malaysia, 11800 Penang, Malaysia. issam@usm.my
Abstract:
A series of new mesogenic azomethine diols were successfully synthesized by condensation reactions between various chloroalkanols and N,N'-bis(4-hydroxy)-benzylidene-o-toluidine (1). The structures of these compounds were confirmed by CHN, FT-IR, (1)H-NMR, and (13)C-NMR spectrophotometer. Their thermotropic liquid crystalline behavior was studied using differential scanning calorimetry (DSC) and polarizing optical microscope (POM). 4,4'-di(4-Hydroxybutoxy)-N-benzylidine-o-tolidine (2a) does not exhibit liquid crystalline properties. A nematic texture was observed for mesogenic diols 2b, and 2d, whereas the diol 2c exhibits a smectic mesophase. The increase of terminal alkyl chain in these mesogenic diols leads to a decrease in the transition temperature.
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