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A Negishi coupling based synthesis of 1,2,4,5-tetra(9-anthryl)benzene derivatives, possessing X-shaped molecular structures, is described. The results of X-ray crystallographic analysis show that two-dimensional highly ordered packing structure of the crystalline state of the unsubstituted derivative is a consequence of intermolecular π-π and CH-π interactions between anthracene units. Photoirradiation of the unsubstituted derivative as a precipitated solution promotes intramolecular [4+4] photocycloaddition reactions between both adjacent pairs of anthracene units to produce a crystalline polycyclic product having a unique 1.700 Å long carbon-carbon single bond. Furthermore, charge-transfer complexes, displaying near-infrared absorption and emission, are generated by co-crystallization of the X-shaped unsubstituted member of the group with electron-acceptor molecules.

We herein describe the development of a mild and selective catalytic aerobic oxidation process of olefins. This catalytic aerobic oxidation reaction was designed based on experimental and spectrosc...

Liquid water exhibits many anomalous physical properties because of its unique structure and hydrogen bonding networks, which were mostly uncovered at the beginning of the 20th century. Because of ...

Flexible and aromatic photofunctional system (FLAP) has been recognized as an emerging class of versatile π-conjugated molecules. Here we report a viscosity-probing function of flapping peryleneimi...

Membrane-integrated nitric oxide reductases (NOR) catalyze the formation of nitrous oxide (N2O) from two NO molecules using two protons and two electrons at a heme/non-heme iron binuclear center. D...

Comprehensive conformational analyses of 1-alkyl-3-methylimidazolium cations ([Cnmim]+ where n = 2–6) were performed by DFT calculations with dispersion correction in the gas phase. The energy diff...

The versatility of the synthesis of sulfonated aromatic polymers using NiBr2 was investigated. The copolymerization of sulfo-dichlorobenzene protected with a neopentyl group was carried out with ch...

Crystalline alumina is a significant inorganic solid that has been utilized as a high-surface-area catalyst support. However, it has been in fact difficult to obtain alumina having high interior po...

The transition behavior of Gibbs monolayers of biomolecules at the air/water interface, and the sustainability of their three-dimensional structure during heating by adsorption/immobilization on in...

A CpRu/Bronsted acid-combined catalyst, CpRu(II)/picolinic acid (PyCOOH), acts as an efficient catalyst for the allyl protection/deprotection of alcohols. This discovery has resulted in the develop...

The speciation and coordination geometries of M(III)-citrate complexes in aqueous solutions, where M denotes Eu, Tb, Lu, or Cm, are studied using potentiometric titration, 1H, and 13C nuclear magnetic resonance spectroscopies. Their photophysical properties are also characterized by time-resolved fluorescence spectra. The formation constants of mononuclear, dinuclear, and trinuclear Lu-citrate species, i.e., [Lu(Cit)2]3−, [Lu2(OH)2(Cit)2]2−, and [Lu3(OH)4(Cit)4]7−, were determined as 9.78 ± 0.30, 3.60 ± 0.30, and 1.02 ± 0.03, respectively, by potentiometric titration in 3.00 M NaClO4 aqueous media. Terminal carboxylic conformation in trinuclear complexes comprised both the five- and six-membered rings at different exchanging rates. Hydration states evaluated for Eu3+ ions are the chemical formula of [Eu(Cit)2(H2O)2.5]3− and [Eu3(OH)4(Cit)4(H2O)3.4]7−. These complexes in aqueous solution have geometrical similarity to the crystal structures in the literature. Furthermore, the entity of the hetero-trinuclea...

We compared adsorption strength of protective agents via ligand exchange of silver nanoparticles synthesized by the improved vacuum evaporation on running oil substrate (VEROS) method. This compari...

We report synthesis and properties of a novel series of ammonium-functionalized perfluoroalkylene/aromatic copolymers. In particular, the effect of number and position of ammonium groups on the properties of the copolymer thin membranes was investigated. Fluorenylidene biphenylene groups were used as a scaffold for the ammonium groups. By controlling the chloromethylation reaction conditions, the ammonium groups could be introduced up to 4.0 per fluorenylidene biphenylene unit, resulting in the ion exchange capacity (IEC) of the resulting copolymers ranging from 1.0 to 1.8 meq g−1. The copolymers provided bendable and transparent membranes by solution casting. The membranes exhibited phase-separated morphology based on the hydrophilic/hydrophobic differences in the copolymer components. A copolymer membrane with IEC = 1.0 meq g−1 showed high hydroxide ion conductivity (ca. 70 mS cm−1) at 80 °C in water and good alkaline stability in 1 M KOH aq. over 1000 h at 60 °C. The membrane showed only minor degradat...

Various amphiphilic block polypeptides having aromatic groups at the C terminal of a Leu-based hydrophobic helical block, poly(sarcosine)-b-(l-Leu-Aib)6-ethylcarbazole, poly(sarcosine)-b-(d-Leu-Aib...

Tuning of localized surface plasmon resonance (LSPR) of metal nanostructures has attracted a great deal of interest, and the controlled syntheses of them have been extensively studied for fine tuning of their LSPR. In this paper, we report widely tunable LSPR from visible to near-infrared of hollow silver nanoshells synthesized by reduction of silver thiocyanate. The silver nanoshell exhibits size- and thickness-dependent LSPR for symmetric dipole mode from visible to near-infrared regions, while the antisymmetric dipole resonance is not changed. By combining characterization of the nanoshells by transmission electron microscopy and theoretical simulation based on discrete dipole approximation, we reveal that the LSPRs are controlled by the size and shell thickness of the nanoshells and also that dimples on the shell surfaces would significantly affect the LSPRs of symmetric dipole, and quadrupole mode for larger nanoshells.

Development of highly efficient and enantioselective hydrophosphonylations of aldehydes and ynones mediated by [5.5]-P-spirocyclic chiral triaminoiminophosphoranes as base catalysts is described. T...

Time-resolved fluorescence spectra of 4′-N,N-diethylamino-3-methoxyflavon in ionic liquids have been measured by using a Kerr gate method and a streak camera at different excitation wavelengths, 37...

Polysaccharide analogues having 2-deoxypsicofuranose as a repeating unit were successfully synthesized by ring-opening metathesis polymerization of 7-oxanorbornene-2,3-diol and dihydroxylation. The...

The stretching properties of a [7]thiaheterohelicene framework, what we call molecular spring, have not been investigated so far, despite a variety of [7]thiaheterohelicene derivatives having very ...

Up to date, the development of TiO2 nanoparticles with well-defined morphology, crystallinity, and high solvent dispersibility has been still a big challenge. In this study, monodisperse and spheri...

The 9,10-bis(3-aryl-2-naphthyl)anthracenes 3 were prepared by the benzannulation reaction of 2-(phenylethynyl)benzaldehyde (1) and the corresponding 9,10-bis(arylethynyl)anthracenes 2 in the presen...