Papers - Yoshioka, Naoki

Synthesis and Magnetic Properties of a Polymeric Nitridochromium(V) Complex with a Tetradentate Schiff Base Ligand

TSUCHIMOTO MASANOBU, YOSHIOKA NAOKI, OHBA SHIGERU

European Journal of Inorganic Chemistry 2001 ( 4 ) 1045 - 1049 2001.03

Research paper (scientific journal), Joint Work, Accepted

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A novel polymeric nitridochromium(V) complex with a Schiff base ligand [CrN(salpn)] [H2(salpn) = N,N′‐disalicylidene‐1,3‐propanediamine] was prepared by photolysis of an azidochromium(III) complex in acetonitrile. X‐ray crystal structure analyses of the starting material {(CH3)2NH2}2[CrCl2(salpn)]Cl (1) and the polymeric complex [CrN(salpn)] (3) were carried out. The orange complex 3 has a linear ···Cr≡N···Cr≡N··· chain structure with the N···Cr distance being 2.508(2) Å. Magnetic data show that 3 has a ferromagnetic intermolecular interaction in the chains (J = +8.4 cm−1).

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Synthesis and Magnetic Properties of Nitronyl Nitroxide radicals Carrying a Purine Ring

吉岡 直樹

Polyhedron 20   1151-1155 2001.03

Research paper (scientific journal), Single Work, Accepted

Formation of Cyclic Trimers and Tetramers of Zinc(II) Pyrazolylporphyrins by Mutual Coordination

IKEDA CHUSAKU, NAGAHARA NORIKO, YOSHIOKA NAOKI, INOUE HIDENARI

New Journal of Chemistry 24   897 - 902 2000.09

Research paper (scientific journal), Joint Work, Accepted

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The self-assembly of zinc(II) porphyrins bearing a pyrazole substituent are reported. 1H NMR, UV/Vis and VPO measurements indicate the formation of a cyclic trimer of zinc(II) pyrazol-4-ylporphyrin and a tetramer of zinc(II) 3,5-dimethypyrazol-4-ylporphyrin by mutual coordination.

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Synthesis and DNA-Binding Properties of Cationic Bisdiazolium Porphyrins

TJAHYONO H. DARYONO, YAMAMOTO TOMOKO, ICHIMOTO SUMITO, YOSHIOKA NAOKI, INOUE HIDENARI

Journal of the Chemical Society, Perkin Transactions 1 2000 ( 18 ) 3077 - 3081 2000.08

Research paper (scientific journal), Joint Work, Accepted

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A pair of 5,15-bisdiazoliumylporphyrins with only two meso-substituents, 5,15-bis(1,3-dimethylimidazolium-2-yl)porphyrin 1b and 5,15-bis(1,2-dimethylpyrazolium-4-yl)porphyrin 2b, has been synthesized. The crowded porphyrin 1b intercalates between base pairs of DNA to stabilize the duplex DNA to thermal denaturation due to its high affinity for DNA. The binding of porphyrin 1b to DNA is an exothermic interaction and enthalpically driven. Porphyrin 1b interacts more strongly with poly(dA-dT)2 than with poly(dG-dC)2, and the interaction is more favorable or selective to AT-rich sites than to GC-rich sites.

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Mechanochemical Reaction of Polymeric Oxovanadium(IV) Complexes with Schiff Base Ligands Derived from 5-Nitrosalicylalde and Diamines

TSUCHIMOTO MASANOBU, HOSHINA GAKUSE, YOSHIOKA NAOKI, INOUE HIDENARI, NAKAJIMA KIYOHIKO, KAMISHIMA MAYOMI, KOJIMA MASAAKI, OHBA SHIGERU

Journal of Solid State Chemistry 153 ( 1 ) 9 - 15 2000.08

Research paper (scientific journal), Joint Work, Accepted

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Light brown [VO(5-NO2salen)]·2H2O (1; H2(5-NO2 salen)=N,N′-di-5-nitrosalicylidene-1,2-ethanediamine) and orange [VO(5-NO2sal-meso-stien)]·0.5H2O (2; H2(5-NO2sal-meso-stien)=N,N′-di-5-nitrosalicylidene-(R,S)(S,R)-1,2-diphenyl-1,2-ethanediamine) which have linear chain structures in the solid state turn dark brown and yellow-brown, respectively, when ground thoroughly in mortars. The IR spectra of 1 and 2 in Nujol mulls show strong V=O stretching bands at 875 and 905 cm−1, respectively. On the other hand, the spectra of the finely ground complexes in Nujol mulls show very weak V=O stretching bands. X-ray powder diffraction patterns of the ground complexes scarcely show diffraction peaks. The spectroscopic and magnetic data suggest that the linear chain structures in the crystals of 1 and 2 are destroyed on grinding to yield the fragments of the polymeric chains.

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Optical Studies of the Monolayer Films of Diazole-Containing Porphyrins at the Air-Water Interface

IKEDA CHUSAKU, TAKASHIMA YUFUKO, IRIE TAKESHI, YOSHIOKA NAOKI, INOUE HIDENARI

Molecular Crystals and Liquid Crystals Science and Technology. Section A. 342 ( 1 ) 81 - 86 2000.08

Research paper (scientific journal), Joint Work, Accepted

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Optical properties of the monolayers of 5-(1-methyliniidazol-2-yl)- 10,15,20-tris(p-octyloxy-phenyl)porphyrin, 5-(1-methylpyrazol-4-yl)-10,15,20-tris(p-octyloxyphenyl)porphyrin and their zinc(II) complexes have been studied. The π-A isotherms and UV-vis spectra have revealed that the zinc(II) complexes form coordination assemblies between peripheral nitrogen atom and central zinc(II) ion at the air-water interface with very tight molecular packing.

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Thermal Decomposition of Prussian Blue Analogues of the Type Fe[Fe(CN)5NO]

INOUE HIDENARI, NARINO SHUICHI, YOSHIOKA NAOKI, FLUCK EKKEHARD

Zeitschrift fur Naturforschung - Section B Journal of Chemical Sciences 55   685 - 690 2000.08

Research paper (scientific journal), Joint Work, Accepted

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The structure and properties of the thermal decomposition products of Fe[Fe(CN)5NO] · x H2O (x = 5 ~ 6) have been studied by Mössbauer and FT-IR spectroscopy, X-ray diffraction, and conductivity measurements. The valence state and coordination environment of the iron ions change dramatically when the nitrosyl ligand is eliminated by heat-treatment under vacuum at 200 °C. The dark blue product obtained by heat-treatment under vacuum at 250 °C is characteristic of the mixed-valence state in Prussian blue analogues. The electrical conductivity of the dark blue product is higher by a factor of 103 than that of the starting material because of the mixed-valence state between Fe(III)[Fe(II)(CN)5] and Fe(II)[Fe(III)(CN)5]. Heat-treatment under vacuum at 350°C yields a new product Fe(II)[Fe(II)(CN)4] the crystal structure of which is different from that of the starting material. The electrical conductivity of the decomposition product obtained at 350 °C is about 105 times higher than that of the starting material.

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DNA Binding of Iron(II) Mixed-Ligand Complexes Containing 1,10-Phenanthroline and 4,7-Diphenyl-1,10-phenanthroline

Mudasir, YOSHIOKA NAOKI, INOUE HIDENARI

Journal of Inorganic Biochemistry 77 ( 3-4 ) 239 - 247 1999.11

Research paper (scientific journal), Joint Work, Accepted

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Absorption spectroscopy and circular dichroism (CD) have been used to characterize the DNA binding of [Fe(phen)3]2+, [Fe(phen)2(DIP)]2+ and [Fe(phen)(DIP)2]2+ where phen and DIP stand for 1,10-phenanthroline and 4,7-diphenyl-1,10-phenanthroline, respectively. Both [Fe(phen)3]2+ and [Fe(phen)2(DIP)]2+ bind weakly to calf thymus DNA (CT-DNA) in an electrostatic mode, while [Fe(phen)(DIP)2]2+ binds more strongly to CT-DNA, possibly in an intercalation mode. The hypochromicity, red shift and Kb increase in the order [Fe(phen)3]2+<[Fe(phen)2(DIP)]2+<[Fe(phen)(DIP)2]2+ in accordance with the increase in size and hydrophobicity of the iron(II) complexes. The thermodynamic parameters obtained suggest that the DNA binding of both [Fe(phen)3]2+ and [Fe(phen)2(DIP)]2+ is entropically driven, while that of [Fe(phen)(DIP)2]2+ is enthalpically driven. A strong CD spectrum in the UV and visible region develops upon addition of CT-DNA into the racemate solution of each iron(II) complex (Pfeiffer effect). This has revealed that a shift in diastereomeric inversion equilibrium takes place in the solution to yield an excess of one of the DNA-complex diastereomers. The striking resemblance of the CD spectral profiles to those of the pure Δ-enantiomer indicates that the Δ-enantiomer of the iron(II) complexes is preferentially bound to CT-DNA. The mechanism of the development of Pfeiffer CD is proposed on the basis of kinetic studies on the DNA binding of the racemic iron(II) complexes.

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Magnetic Properties of Nitronyl Nitroxide Derivatives Bearing N-H Site: an Approach to Ferromagnetic Self-Assemblies Using Hydrogen Bond

YOSHIOKA NAOKI, MATSUOKA NAOKI, IRISAWA MUNETOSHI, OHBA SHIGERU, INOUE HIDENARI

Molecular Crystals and Liquid Crystals Science and Technology. Section A. Vol. 334 ( 1 ) 239 - 246 1999.11

Research paper (scientific journal), Joint Work, Accepted

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Abstract
Nitronyl nitroxide derivatives bearing NH site, imidazolyl-2-nitronyl nitroxide (Im-NN), 4(5)-methyl-imidazolyl-2-nitronyl nitroxide (MeIm-NN), and benzimidazolyl-2-nitronyl nitroxide (BIm-NN) were synthesized, and were self-assembled by hydrogen bonding at NH site with nitrogen atom on imidazole ring or oxygen atom of nitroxide moiety. Ferromagnetic intermolecular interactions were observed in MeIm-NN and BIm-NN. The magnetic interaction can be rationally explained by McConnell model.

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Cationic porphyrins bearing diazolium rings: synthesis and their interaction with calf thymus DNA

TJAHJONO H. DARYONO, YOSHIOKA NAOKI, INOUE HIDENARI

Biochimica et Biophysica Acta 1472 ( 1-2 ) 333 - 343 1999.10

Research paper (scientific journal), Joint Work, Accepted

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Two novel cationic porphyrins bearing five-membered rings at the meso-positions, meso-tetrakis(1,3-dimethylimidazolium-2-yl)porphyrin (H2TDMImP) and meso-tetrakis(1,2-dimethylpyrazolium-4-yl)porphyrin (H2TDMPzP), have been synthesized. These two compounds interact with calf thymus DNA (CTDNA) in different binding modes from that of meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (H2TMPyP). H2TDMImP outside binds to the minor groove of CTDNA while H2TDMPzP intercalates into CTDNA. These two novel cationic porphyrins strongly bind to CTDNA even at high ionic strength and the binding constant of H2TDMPzP to CTDNA is comparable to that of H2TMPyP. The binding of H2TDMImP to CTDNA is enthalpically driven. The favorable free energy changes in binding of H2TDMPzP to CTDNA come from the large negative enthalpy changes accompanied by small positive entropy changes.

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Self-Assembly of Monopyrazolylporphyrins by Hydrogen Bonding in Solution

IKEDA CHUSAKU, NAGAHARA NORIKO, MOTEGI EIKO, YOSHIOKA NAOKI, INOUE HIDENARI

Chemical Communications Vo1 1999   1759 - 1760 1999.09

Research paper (scientific journal), Joint Work, Accepted

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The self-associated structures of two noble meso-(monopyrazolyltritolyl)porphyrins synthesized via their NH-protected precursors have been studied by 1H NMR, FT-IR and ESI MS measurements; meso-(pyrazol-4-yl)porphyrin and meso-(3,5-dimethylpyrazol-4-yl)porphyrin form a dimer and a tetramer, respectively, in solution due to intermolecular hydrogen bonding between pyrazole units.

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Iron(II) and Nickel(II) Mixed-Complexes Containing 1,10-Phenanthroline and 4,7-Diphenyl-1,10-phenanthroline

MUDASIR, YOSHIOKA NAOKI, INOUE HIDENARI

Transition Metal Chemistry Vol. 24 ( 2 ) 210 - 217 1999.06

Research paper (scientific journal), Joint Work, Accepted

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Two types of mixed-ligand complexes, i.e. [M(phen)2 (dip)]2+ and [M(phen)(dip)2]2+ (M = iron(II) and nickel(II); phen = 1,10-phenanthroline and dip = 4,7-diphenyl-1,10-phenanthroline) have been prepared from their related tris-complexes, [M(phen)3]2+ by ligand substitution, and isolated by semi-preparative HPLC. Elemental and chromatographic analyses confirm the purity of the isolated complexes while u.v./vis and i.r. spectra were used to identify and characterize them. 1H-n.m.r. and room temperature Mössbauer spectra of the iron(III) complexes were also measured and the results are discussed. In addition, our preliminary results on hypochromicity in the MLCT band and circular dihroism (CD) emerging in the u.v./vis region upon addition of CT(calf thymus)-DNA to the racemic complexes indicated that the iron(II) mixed-ligand complexes interact with CT-DNA.

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Polymerization of (p-Vinylphenyl) hydrogalvinoxyl and Formation of a Stable Polyradical Derivative

KANEKO TAKASHI, TATSUMI HIROYUKI, AOKI TOSHIKI, OIKAWA EIZO, YOSHIOKI HAJIME, YOSHIOKA NAOKI, TSUCHIDA EISHUN, NISHIDE HIROYUKI

Journal of Polymer Science, Part A Polymer Chemistry 37 ( 2 ) 189 - 198 1999.01

Research paper (scientific journal), Accepted

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4‐[(3,5‐Di‐tert‐butyl‐4‐hydroxyphenyl)(3,5‐di‐tert‐butyl‐4‐oxo‐cyclohexa‐ 2,5‐dienylidene)methyl]styrene (abbreviated as (p‐vinylphenyl)hydrogalvinoxyl) was polymerized using AIBN as an initiator to give a bright yellow polymer with Mw = 3.2 × 104. The polymer was oxidized to give the corresponding polyradical derivative, whose spin concentration could be increased up to about 70 mol % depending on oxidative conditions. ESR signal line‐width in the solid state was greatly increased below 200 K for the polyradical with a high spin concentration (> 50 mol %). The magnetization and magnetic susceptibility indicated weak antiferromagnetic interaction among the radical sites.

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Magnetic Properties of Polynuclear Oxovanadium(Ⅳ) Complexes with Tetradetate Schiff Base Ligands

TSUCHIMOTO MASANOBU, YOSHIOKA NAOKI

Chemical Physics Letters 297 ( 1-2 ) 115 - 120 1998.11

Research paper (scientific journal), Joint Work, Accepted

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Temperature dependence measurements of magnetic susceptibilities and low-temperature magnetization of tetradentate Schiff base–oxovanadium(IV) complexes, [VO(salpn)] (1), [VO(5-NO2salen)]·2H2O (2), and [VO(3-EtOsal-meso-stien)]·H2O (3) were carried out. Orange 1 and brown 2, which take linear chain structures (VO⋯VO⋯) in the solid state, show dominant ferromagnetic intermolecular interactions (J=+5.2 and +5.7 cm−1, respectively) on which very weak antiferromagnetic interactions between the chains are superimposed. However, green 3, which takes a fairly elongated linear chain structure (V⋯O distance: 4.060(2) Å) in the crystal, shows an isolated doublet state.

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Magnetic Properties of Nitronyl Nitroxide Derivatives Bearing N-H Site: An Approach to Ferromagnetic Self-Assemblies Using Hydrogen Bond

Naoki Yoshioka, N. Matsuoka, Munetoshi Irisawa, Shigeru Ohba, Hidenari Inoue

Molecular Crystals and Liquid Crystals 334   239-246 1998.10

Research paper (scientific journal), Joint Work, Accepted

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N-H水素結合部位を有するニトロニルニトロキシドラジカルの磁気特性に対するイミダゾール導入置換基の影響を報告した。（９頁）

Mossbauer Spectroscopic Characterization of the Light-Induced Mixed-Valence State in Fe[Fe(CN)5NO]・xH2O

INOUE HIDENARI, YOSHIOKA NAOKI, MORIOKA YOSHIYUKI

Hyperfine　Interactions (C) 3   113 - 116 1998.08

Research paper (scientific journal), Joint Work, Accepted

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Fe[Fe(CN)5NO]・xH2Oに光照射した際に観測される磁気特性の変化を報告した.

Light-Induced Mixed-Valence State of FeII[Fe(CN)5NO]・xH2O

MORIOKA YOSHIYUKI, HISAMITSU TAKA-AKI, INOUE HIDENARI, YOSHIOKA NAOKI, TOMIZAWA HIROSHI, MIKI EI-ICHI

Bulletin of the Chemical Society of Japan 71 ( 4 ) 837 - 844 1998.04

Research paper (scientific journal), Joint Work, Accepted

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A long-living metastable state is produced in FeII[Fe(CN)5NO]·xH2O by an irradiation of 488 nm light at 200 K. A strong near-infrared band of about 10000 cm−1 and a ν(CN) band at 2070 cm−1 that newly appear in the metastable state point to development of the mixed-valence state analogous to Prussian blue. An iron-to-nitrosyl charge transfer in pentacyanonitrosylferrate(2−), [Fe(CN)5NO]2−, explains the formation of the mixed-valence state, because the charge transfer causes a pair of iron(II) and iron(III) atoms bridged by CN− that has the same local structure as Prussian blue. In addition to the formation of the metastable state, the prolonged irradiation causes an irreversible change of FeII[Fe(CN)5NO]·xH2O and leads to the formation of a photoproduct. The photoproduct also has infrared spectra characteristic of the mixed-valence state. Mössbauer spectra of the photoproduct show that a low-spin iron ion in pentacyanonitrosylferrate(2−) is divalent and a high-spin iron outside of pentacyanonitrosylferrate(2−) is trivalent. Therefore, the charge-transfer between the two non-equivalent iron ions is thought to follow the intra-molecular charge transfer in pentacyanonitrosylferrate(2−).

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Reversed-Phase High-Performance Liquid Chromatography of Iron(II) and Copper(II) Chelates with 4,7-diphenyl-1,10-phenanthroline disulfonate

MUDASIR, ARAI MEIKO, YOSHIOKA NAOKI, INOUE HIDENARI

Journal of Chromatography A 799 ( 1-2 ) 171 - 176 1998.03

Research paper (scientific journal), Joint Work, Accepted

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The chromatographic behaviour of negatively-charged iron(II) and copper(II) chelates with 4,7-diphenyl-1,10-phenanthroline (bathophenanthroline) disulfonate (BPS) on a reversed-phase Inertsil ODS-2 column was studied by using methanol–water (60:40, v/v) containing 0.02 M tetramethylammonium bromide (TMAB) and 0.025 M tris(hydroxymethyl)aminomethane (Tris)–HCl at pH 7.5 as a mobile phase. The possibility that the hydrophilic Tris–HCl buffer also serves as a counter ion together with TMAB was briefly discussed. Chromatographic parameters influencing the separation of the chelates were optimized. The method was successfully applied to indirectly determine iron(II) and iron(III) contents in natural water. Nickel(II) ion and possibly organic pollutants interfere with the present method.

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Synthesis and Magnetic Property of Stable Organic Radicals Bearing Imidazole Ring

YOSHIOKA NAOKI, IRISAWA MUNETOSHI, MOCHIZUKI YUICHIRO, AOKI TAKASHI, INOUE HIDENARI

Molecular Crystals and Liquid Crystals Science and Technology. Section A. 306   403 - 408 1997.12

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Three imidazole derivatives with stable radical groups at 2-position were prepared and their magnetic property were characterized. The effect of NH hydrogen bonding site was also discussed.

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Synthesis and Magnetic Properties of　Metal Complexes with Chelating Nitronyl Nitroxide and Imino Nitroxide

YOSHIOKA NAOKI, IRISAWA MUNETOSHI, AOKI TAKASHI, AIZAWA NAOYUKI, INOUE HIDENARI, OHBA SHIGERU

Molecular Crystals and Liquid Crystals Science and Technology Section A 306   397 - 402 1997.12

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Several metal complexes of chelating pyridyl nitronylnitroxide, imidazolyl nitronylnitorxide, and imidazolyl iminonitroxide were synthesized and their magnetic properties were characterized.

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