Synthesis and Liquid Crystalline Properties of Novel Triazene-1-oxide Derivatives

Abstract

A new group of compounds, C₆H₅-N(O)=N-NH-C₆H₄-C(O)-O-C₆H₄-CH=N-C₆H₄-OR, ( 1 ), [R = n-alkyl group; 1a (R = C₇H₁₅ ) to 1h (R = C₁₄H₂₉)], has been designed and synthesized to develop triazene-1-oxide based liquid crystals. All the compounds have been characterized on the basis of their spectral data. Their thermal behavior has been examined and found to exhibit thermotropic liquid crystalline behavior over a wide range of temperature. All members of this family uniformly show nematic phase behavior on melting up to the clearing point during heating as well as on phase entering up to the solidification during cooling. An odd–even effect on transition temperatures has been observed during heating as well as cooling.

Keywords:

• ester
• imine
• liquid crystal
• nematic
• triazene-1-oxide

ACKNOWLEDGMENTS

The financial support (SR/S1/IC-08/2007) from DST, Government of India, is gratefully acknowledged. We thank CSIR (India) for the award of a fellowship (PD) and UGC (New Delhi) for Special Assistance Programme to our Department.