Benzylidenehydrazine based room temperature columnar liquid crystals

We report on the synthesis and investigation of self-assembly properties of new benzylidenehydrazine based compounds, namely N-(2,3,4-tridodecyloxybenzylidene)-3,4,5-N'-trialkoxybenzoylhydrazines. They were confirmed to exhibit wide ranges of room temperature hexagonal columnar liquid crystalline phases (Col(h)) as evidenced by optical polarizing microscope (OPM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies. Helical organization was confirmed for the Col(h)* phase of a compound with chiral tails. More generally, combining the 2,3,4- and 3,4,5-substitution patterns of aromatic cores in one molecule provides a new way to low melting columnar LC materials with wide phase ranges.