Benzimidazole derivatives: selective fluorescent chemosensors for the picogram detection of picric acid.

1,3,5-Tri(1H-benzo[d]imidazol-2-yl)benzene derivatives, as a new kind of fluorescent chemosensor for the detection of nitroaromatic explosives, are designed and synthesized by simple N-hydrocarbylation. Among 16 obtained compounds, compound 4g has the best capability for detection of picric acid (PA), having good selectivity and high sensitivity. The detection of PA with 4g solution-coated paper strips at the picogram level is developed. A simple, portable, and low-cost method is provided for detecting PA in solution and contact mode.

Design, synthesis, and characterization of 1,3,5-tri(1H-benzo[d]imidazol-2-yl)benzene-based fluorescent supramolecular columnar liquid crystals with a broad mesomorphic range.

A new kind of supramolecular columnar liquid crystal T-A with a broad mesomorphic range (up to 164.9 °C), good thermal stability, and strong fluorescence is designed and formed by the H-bonding between 1,3,5-tri(1H-benzo[d]imidazol-2-yl)benzene (T) and serial gallic acid derivatives (A). Two components are easily available because of simple routes, common reactions, high yields, commercial starting materials, and inexpensive catalysts. The introduction of the 1,2,3-triazole structure into component A makes the textures different and is slightly disadvantageous for the T-A complexes.

Electrophoretic deposition polymerization of diacetylenes with tunable structure.

Serial novel chiral polydiacetylenes (PDAs) are efficiently prepared at room temperature by the controllable electrophoretic deposition of diacetylenes with tunable structure as designed from easily available starting materials. The colorimetrically reversible properties of PDAs in the range between 25 and 85 °C are influenced by the different amino acid moiety in the PDAs as anticipated. The PDA containing aromatic ring is much better for the colorimetrically reversible properties, while irreversible thermochromism is displayed for the PDA with the structure of the longer methylene units in the main chain of amino acid moiety.

(5S)-3-Chloro-4-(2,5-dihydro-1H-pyrrol-1-yl)-5-[(1R,2S,5R)-2-isopropyl-5-methyl-cyclo-hex-yloxy]furan-2(5H)-one.

The title compound, C(18)H(26)ClNO(3), was obtained via a tandem asymmetric Michael addition-elimination reaction of 3,4-dichloro-5-(S)-(l-menth-yloxy)furan-2(5H)-one and 2,5-di-hydro-1H-pyrrole in the presence of potassium fluoride. In the mol-ecule, the nearly planar dihydro-pyrrole ring [maximum atomic deviation = 0.019 (3) Å] is oriented at a dihedral angle of 10.73 (8)° to the the nearly planar furan-one ring [maximum atomic deviation = 0.011 (2) Å]; the cyclo-hexane ring adopts a chair conformation. In the crystal, mol-ecules are linked via weak inter-molecular C-H⋯O hydrogen bonds, forming supra-molecular chains running along the b axis.