Pyrrolic and polypyrrolic anion binding agents

Structure, dynamics and transport properties of microemulsions

A review of current trends and advances in modern bio-analytical methods: chromatography and sample preparation.

Sensing of metal ions and anions is of great importance because of their widespread distribution in environmental systems and biological processes. Colorimetric and fluorescent chemosensors based on organic molecular species have been demonstrated to be effective for the detection of various ions and possess the significant advantages of low cost, high sensitivity, and convenient implementation. Of the available classes of organic molecules, porphyrin analogues possess inherently many advantageous features, making them suitable for the design of ion chemosensors, with the targeted sensing behavior achieved and easily modulated based on their following characteristics: (1) NH moieties properly disposed for binding of anions through cooperative hydrogen-bonding interactions; (2) multiple pyrrolic N atoms or other heteroatoms for selectively chelating metal ions; (3) variability of macrocycle size and peripheral substitution for modulation of ion selectivity and sensitivity; and (4) tunable near-infrared emission and good biocompatibility. In this Review, design strategies, sensing mechanisms, and sensing performance of ion chemosensors based on porphyrin analogues are described by use of extensive examples. Ion chemosensors based on normal porphyrins and linear oligopyrroles are also briefly described. This Review provides valuable information for researchers of related areas and thus may inspire the development of more practical and effective approaches for designing high-performance ion chemosensors based on porphyrin analogues and other relevant compounds.

Development of Ion Chemosensors Based on Porphyrin Analogues

The chemical interpretation and practice of linear solvation energy relationships in chromatography

The structure of acetonitrile−water mixtures has been investigated by X-ray diffraction with an imaging plate detector and IR spectroscopy over a wide range of acetonitrile mole fractions (0.0 ≤ XAN ≤ 1.0). Reichardt ETN and Sone-Fukuda DII,I values were also measured for the mixtures. It has been found from the X-ray data that in pure acetonitrile an acetonitrile molecule interacts with two nearest neighbors by antiparallel dipole−dipole interaction together with a small shift of the two molecular centers and that two acetonitrile molecules in the second-neighbor shell interact with a central molecule through parallel dipole−dipole interaction. Thus, acetonitrile molecules are alternately aligned to form a zigzag cluster. On addition of water into pure acetonitrile, water molecules interact with acetonitrile molecules through a dipole−dipole interaction in an antiparallel orientation. The IR spectra of O−D and C⋮N stretching vibrations, observed for mixtures of acetonitrile AN and water containing 20% D2...

Liquid Structure of Acetonitrile−Water Mixtures by X-ray Diffraction and Infrared Spectroscopy

Fourteen water-miscible polar solvents were investigated for the separation from their aqueous solutions by salting-out using sodium chloride (4mol dm-3). The following solvents showed the phase separation: acetone, acetonitrile, 1, 4- dioxane, tetrahydrofuran, 1-propanol, and 2-propanol. The chemical properties of the separated organic solvents were determined by measuring ET(30)(=1.196×105/λ (kJmol 1)) and DII.I(=1.196×105(λII-1-λI-1)(kJ mol-1))values from the spectral change of 2, 6-Biphenyl-4-(2, 4, 6-triphenylpyridinio)phenolate (DTP) and bis(1, 3-propanediolato)vanadium(IV) (VO(acac)2), where λ, λI, and λII denote the absorption maximum wavelengths (nm) of DTP and VO(acac)2. Solvent properties of acetone, acetonitrile, 1, 4-dioxane, and tetrahydrofuran were dramatically altered by the salting- out. Acceptability of the phase-separated solvents increased due to the dissolution of water molecules having large acceptor numbers. The ion-pair complex of tris(1, 10-phenanthroline)iron(II) chloride was easily extracted into the phase-separated acetonitrile by the salting-out. Some metal chelates of 1-(2-pyridylazo)-2-naphthol (Hpan) and 8- quinolinol (Hox), 5, 10, 15, 20-tetraphenylporphyrin (H2tpp), and ionic species (H2ox+, ox-, and H4tpp2+) were also extracted into 1, 4-dioxane. The raised donor and acceptor abilities of the phase-separated solvents allowed application to solvent extraction.

Chemical Properties of Water-Miscible Solvents Separated by Salting-out and Their Application to Solvent Extraction

Equilibrium study of ion-pair extraction of a cationic water-soluble porphyrin [5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin, H2tmpyp4+] and its metalloporphyrins (MP) into the acetonitrile layer, separated by addition of sodium chloride (4.00 mol dm-3) to a 1:1 (v/v) acetonitrile−water mixed solvent, was carried out to develop a new and useful method for the determination of a subnanogram amount of copper(II). M denotes Zn2+, Cu2+, Co3+, Fe3+, and Mn3+, and P2- is porphyrinate ion. The extraction and dissociation constants of the ion-pair complexes, defined by Kex = [MP(ClO4)4]org[MP4+]aq-1[ClO4-]aq-4, Kdis,1 = [MP(ClO4)3+]org[ClO4-]org[MP(ClO4)4]org-1, and Kdis,2 = [MP(ClO4)22+]org[ClO4-]org[MP(ClO4)3+]org-1, were determined by taking into account the partition constant of sodium perchlorate (KD = 1.82 ± 0.01). The equilibrium constants were found to be KexKdis,1 = (7.2 ± 1.3) × 104, (6.4 ± 0.9) × 104, (1.35 ± 0.13) × 105, (4.8 ± 0.6) × 103, (1.23 ± 0.05) × 104, and (1.42 ± 0.07) × 103 at 25 °C...

Ion-Pair Extraction of Metalloporphyrins into Acetonitrile for Determination of Copper(II).

Phase separation of acetonitrile−water mixtures by addition of NaCl has been studied on the molecular level by large-angle X-ray scattering (LAXS) and small-angle neutron scattering (SANS) methods. A phase diagram of acetonitrile−water−NaCl mixtures at 298 K has shown that phase separation occurs over a wide range of acetonitrile mole fraction (xAN) of ∼0.1 < xAN ≤ ∼0.7, where the microheterogeneity of the mixtures occurs. The radial distribution functions obtained by the LAXS measurements have revealed that before phase separation the amounts of preferentially hydrated Na+ and Cl- gradually increase with increasing NaCl concentration and that the number of linear hydrogen bonds among water molecules increases when the concentration of NaCl increases. After phase separation of the acetonitrile−water−NaCl mixtures the structures of the acetonitrile-rich phase are very similar to those of the acetonitrile−water binary mixtures at the corresponding acetonitrile mole fractions. The water-rich phase which cont...

Large-Angle X-ray Scattering and Small-Angle Neutron Scattering Study on Phase Separation of Acetonitrile−Water Mixtures by Addition of NaCl

Selective extraction of thallium(III) in the presence of gallium(III), indium(III), bismuth(III) and antimony(III) by salting-out of an aqueous mixture of 2-propanol

Jun Nishimoto

Papers

Liquid Structure of Acetonitrile−Water Mixtures by X-ray Diffraction and Infrared Spectroscopy

Chemical Properties of Water-Miscible Solvents Separated by Salting-out and Their Application to Solvent Extraction

Ion-Pair Extraction of Metalloporphyrins into Acetonitrile for Determination of Copper(II).

Large-Angle X-ray Scattering and Small-Angle Neutron Scattering Study on Phase Separation of Acetonitrile−Water Mixtures by Addition of NaCl

Selective extraction of thallium(III) in the presence of gallium(III), indium(III), bismuth(III) and antimony(III) by salting-out of an aqueous mixture of 2-propanol