ao8b00496_si_001.pdf (2.65 MB)
Transforming a C3‑Symmetrical Liquid Crystal to a π‑Gelator by Alkoxy Chain Variation
journal contribution
posted on 2018-04-20, 16:51 authored by Anjamkudy Sandeep, Vakayil K. Praveen, D. S. Shankar Rao, S. Krishna Prasad, Ayyappanpillai AjayaghoshRational
understanding of the structural features involving different
noncovalent interactions is necessary to design a liquid crystal (LC)
or an organogelator. Herein, we report the effect of the number and
positions of alkoxy chains on the self-assembly induced physical properties
of a few π-conjugated molecules. For this purpose, we designed
and synthesized three C3-symmetrical molecules
based on oligo(p-phenylenevinylene), C3OPV1–3. The self-assembly properties of these molecules are studied
in the solid and solution states. All of the three molecules follow
the isodesmic self-assembly pathway. Upon cooling from isotropic melt, C3OPV1 having nine alkoxy chains (−OC12H25) formed a columnar phase with two-dimensional rectangular lattice
and retained the LC phase even at room temperature. Interestingly,
when one of the −OC12H25 groups from
each of the end benzene rings is knocked out, the resultant molecule, C3OPV2 lost the LC property, however, transformed as a gelator in toluene
and n-decane. Surprisingly, when the −OC12H25 group from the middle position is removed,
the resultant molecule C3OPV3 failed to form either the LC or the gel phases.