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Updated: Jul 19, 2025

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Solvent-Dependent Conformational Switching of N-Methyl-N,N'-diarylsquaramide
Kimiko Tanaka1, Fumi Takeda1, Midori Kanda1
1Department of Chemistry, Faculty of Science, Ochanomizu University, 2-1-1 Otsuka, Bunkyo-ku, Tokyo 112-8610, Japan.
Abstract:
N,N'-Diarylsquaramide and N,N'-dialkylsquaramide are conformationally stable linkers with extended (trans, trans) and folded (cis, cis) structures, respectively, independently of external conditions. Here, we show that N-monomethylated N,N'-diarylsquaramides generally take a (trans, cis) structure in the crystal but show a solvent-dependent conformational equilibrium in solution. In particular, the stable conformer of N-methyl-N,N'-bis(1-naphthyl)squaramide (1f) changes depending upon the solvent. Thus, aromatic N-monomethylated squaramides could find application as components of environment-responsive molecular switches.
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