Highly regio-/stereoregular (trans-head-to-tail) polymers with amide side chains on every eighth backbone carbon were successfully synthesized by ring-opening metathesis polymerization (ROMP) of 3-substituted cis-cyclooctene (3RCOE) using Grubbs second-generation catalyst (G2). Regioregular linear ethylene–acrylamide copolymers were also prepared via hydrogenation of the obtained poly­(3RCOE)­s. The thermal properties and solubility of the obtained polymers were strongly influenced by the presence of amide hydrogen in the side chains, the presence of unsaturated bonds in the carbon backbone, and the side chain density. The presence of amide hydrogen in the side chains resulted in the formation of crystalline polymers and the lack of solubility of these polymers in common organic solvents. In contrast, the absence of amide hydrogen in the side chains led to the formation of amorphous polymers exhibiting good solubility in common organic solvents, and decreasing values of T g were observed for amorphous polymers as a result of the saturation of double bonds in the backbone via hydrogenation.

Chiral induction properties of achiral bisurea derivatives by binding tetrabutylammonium salts of N-acetylated chiral carboxylates (Ac-AlaO–, Ac-ValO–, Ac-LeuO–, and Ac-PheO–) was studied. Ultraviolet–visible titrations showed 1:1 complex formation between the bisureas and the carboxylates. The calculated association constants of cyclic bisurea (1a) were 5–10 times larger than those of the acyclic derivative (2), and 1a showed the highest binding affinity for Ac-LeuO–. While circular dichroism (CD) of both 1a and 2 was induced upon the addition of chiral carboxylates, the CD intensity of 1a was greater than that of 2. Especially, the intensity induced by chiral Ac-LeuO– was the greatest. 1H nuclear magnetic resonance titrations and density functional theory (DFT) calculations showed the cooperative hydrogen bonds of four urea N–Hs and the carboxylate group and the CH−π interactions between a naphthyl unit of 1a and the methyl moieties of Ac-LeuO–. Furthermore, DFT calculations suggested that the twisted anticlockwise conformation of 1a would be dominantly induced by Ac-d-LeuO–. The CD intensity changes of 1a showed a good linear relationship with the enantiomeric excess (ee) values of Ac-LeuO–; therefore, 1a could be utilized as a stereodynamic chiral probe for determining the ee of chiral anions.

Chiral recognition abilities of tetraamide-based receptors 1 and 2 bearing l-serine and l-threonine as recognition sites, respectively, and terminal pyrenyl groups as signaling units for enantiomers of biologically important N-acetyl amino acid tetrabutylammonium salts were studied in acetonitrile. The receptors showed ratiometric fluorescence changes upon the addition of chiral guest anions. The binding constants for amino acid derivatives were in the 104–105 mol−1 dm3 range. The chiral discrimination abilities (K11,D/K11,L) of 1 and 2 were significantly large, for instance K11,D/K11,L for Ac-Leu-O− were found to be 3.9 and 4.6, respectively. The complex structures were evaluated by 1H NMR titrations and DFT calculations implying that the effective hydrogen bond formations by six N-H and O-H groups and a CH-π interaction of the acetyl group of d-enantiomer with a terminal pyrenyl group of the receptor.

Silanediols possess unique and complementary catalytic activity in reactions that are likely to proceed through anion binding. This article directly compares silanediols, thioureas, and squaramides in three separate anion-binding processes. The catalytic abilities of select members of each family are directly correlated to association constants.

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