The cation-directed self-assembly process has emerged as a fascinating approach for constructing supramolecular architectures and manifested a diverse range of assembly related applications. Herein, we synthesized a macrocyclic structure containing bis-amidopyridine and photopolymerizable diacetylene template, PyMCDA. Owing to the metal coordination affinity of bis-amidopyridine and the π−π stacking characteristic of diacetylene template and complementary to the cyclic molecular framework, Cs + -directed organic nanotubes are generated via unidirectional selfassembly of PyMCDA. The monomeric PyMCDA nanotubes are transformed into the covalently cross-linked chromogenic polydiacetylene nanotubes (PyMCPDA-Cs + ) by UV-promoted topochemical polymerization. The result of a metal−ligand coordination characteristic, geometric parameters in solid-state assemblies, and topochemical polymerization behavior reveals a generation of Cs + ion inserted nanotubes. Interestingly, PyMCDA-Cs + nanotubes display thermochromic property with a brilliant blue-to-red color transition.

Creation of tubular structures through the self-assembly of macrocyclic molecules has gained great attention in the chemical, biochemical, and material sciences. Through a designed introduction of two octaethylene oxide and two diacetylene moieties, we prepared a macrocycle MCDA–BisOEG, which is water-soluble and photopolymerizable and displays a lower critical solution temperature (LCST) behavior. The hydrodynamic diameter of MCDA–BisOEG, measured by dynamic light scattering method, was ca. 6.5 nm at 25 °C and increased sharply to ca. 2 μm at temperatures above 34 °C (LCST). Below the LCST, the macrocycle in aqueous solution formed tubular structures, which upon UV irradiation generated blue conjugated polydiacetylene (PDA) nanotubes. The PDA nanotubes undergo a blue-to-red color change when heated above the LCST. No polymerization occurs above the LCST owing to the disordered aggregation of the diacetylene monomer. This is the first example of the preparation of a macrocycle-based, thermoresponsive, conjugated polymer nanotube in aqueous solution.

Owing to their capability of forming extensive hydrogen bondings and the facile introduction of chirality, cyclic dipeptides (CDPs) have gained great attention as scaffolds for functional supramolecules. Surprisingly, introduction of a photopolymerizable diacetylene (DA) moiety to the CDP afforded nanotubular structures with enhanced stability and reversible thermochromism. A series of CDP-containing DAs (CDP-DAs) are prepared by coupling 10,12-pentacosadiynoic acid with CDPs, cyclo(-Gly-Ser) and cis/trans cyclo(-Ser-Ser). Fabrication of CDP-DA self-assemblies in a polar chloroform and methanol solvent mixture affords nanotubes comprising single-wall and multiwall structures. The self-assembly behavior and morphology characteristic are examined by scanning electron microscopy and transmission electron microscopy. Next, X-ray diffraction analysis confirms well-ordered lamellar structures with a perfect agreement with the bilayer formation leading to the tubular structure via lamellar scrolling behavior. Upon UV irradiation, monomeric CDP-DA tubular assemblies result in the blue-colored CDP/polydiacetylene (PDA) nanotubes. Interestingly, CDP/PDA nanotubes exhibit a reversible blue-to-red color change for over 10 consecutive thermal cycles. The CDP-DA/PDA supramolecular system demonstrates potential applications in developing stimulus-responsive functional materials.

Owing to its high conductivity, solution processability, mechanical flexibility, and transparency, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been extensively explored for use in functional devices including solar cells, sensors, light-emitting diodes, and supercapacitors. The ability to fabricate patterned PEDOT:PSS on a solid substrate is of significant importance to develop practical applications of this conducting polymer. Herein, we describe a new approach to obtain PEDOT:PSS patterns that are based on a polymerizable supramolecular concept. Specifically, we found that UV irradiation of a photopolymerizable diacetylene containing PEDOT:PSS film followed by development in deionized water and subsequent treatment with sulfuric acid (glass and silicon wafer) or formic acid (PET) produces micron-sized PEDOT:PSS patterns on solid substrates. The newly designed photolithographic method, which can be employed to generate highly conductive (>1000 S/cm) PEDOT:PSS patterns, has many advantages including the use of aqueous process conditions, a reduced number of process steps, and no requirement for plasma etching procedures.

The title compound, 2-(4-fluoro-3-nitrophenyl)-6-(4-methoxyphenyl)­imidazo[2,1-b]-1,3,4-thiadiazole (3) was obtained by the condensation of 5-(4-fluoro-3-nitrophenyl)-[1,3,4]thiadiazol-2-ylamine (1) with 4-methoxyphenacyl bromide (2). The newly prepared imidazo[2,1-b]-1,3,4-thiadiazole derivative (3) was characterized by IR, 1H-NMR, 13C-NMR and LCMS spectral data