Papers - IWATSUKI Satoshi
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Detailed Reaction Mechanism of Anthracene-Bridged bis(3-Pyridiniumboronic Acid) Chemosensor with D-Glucose Reviewed International journal
Rei Tanaka, Keigo Matsuo, Shota Suzuki, Gento Mikami, Yota Suzuki, Tomoaki Sugaya, Satoshi Iwatsuki, Masahiko Inamo, Koji Ishihara
ChemistrySelect 9 e202304924 2024.3
Joint Work
Detailed reaction mechanisms of 4-(N-methyl)pyridinium boronic acid (1) and anthracene-bridged bis(pyridinium boronic acid) compounds (diboronic acids 2 and 3) with D-glucose were kinetically investigated in aqueous methanolic solutions. The crystal structure of diboronic acid 3 was determined using X-ray crystallography. The pKa values of the two boronic acid moieties of diboronic acid (2 or 3) differed by one unit, indicating electronic interactions between the two boronic acid moieties. The kinetics of the reaction of boronic acid 1 with D-glucose showed that both trigonal boronic acid and tetrahedral boronate ions were reactive with D-glucose. UV-Vis spectrophotometry and 1HNMR spectrometry of the reactions of phenylboronic acid with some model compounds of D-glucose showed that the reactive moiety of α-D-glucofuranose towards phenylboronic acid was not the 1,2-diol site, but the 3,5,6-triol site. In the reactions of diboronic acids 2 and 3 with D-glucose, the 3,5,6-triol site of α-D-glucofuranose reacts first with one of the two equivalent boronic acid moieties of diboronic acid to form a 3,5-bicoordinate intermediate as a rate-determining step, followed by the reaction of the 1,2-diol site of α-Dglucofuranose with another boronic acid moiety of diboronic acid to form the final 1,2 : 3,5-tetracoordinate cyclic compound as a fast step.
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Twisted Intramolecular Charge Transfer-Based Fluorometric Detection of D-fructose by Boronic Acid-Containing BF2-β-Diketonate Complexes Reviewed
Hitomi Saito, Yukika Sobue, Tomoaki Sugaya, Satoshi Iwatsuki, Masahiko Inamo, Koji Ishihara
ChemPhotoChem 7 e202200271 2023.7
Joint Work
Novel BF2-β-diketonate complexes 1–4 bearing phenylboronic acid moieties and methoxyphenyl or dimethylaminophenyl groups were synthesized and their photophysical properties, pH response, and reactivity to D-fructose were evaluated. Complexes 1 and 2 bearing a methoxyphenyl group luminesced with high intensity in a range of non-polar to polar solvents, except in DMSO, whereas complexes 3 and 4 containing a dimethylaminophenyl group with twisted intramolecular charge transfer (TICT) properties showed a dramatic decrease in luminescence intensity with increasing solvent polarity. The luminescence intensity of complexes 1 and 2 decreased with increasing pH due to intermolecular vibration which associated with hydrogen bonding between the complexes and solvent water molecules, whereas it increased when they reacted with D-fructose due to the suppression of the intermolecular vibration. In contrast, the luminescence intensity of complexes 3 and 4 increased with increasing pH and upon reaction with D-fructose due to the loss of its TICT properties. The photophysical properties of complexes 1–4 and the TICT properties of complexes 3 and 4 were supported by density functional theory
calculations. -
Asymmetrical Platinum and Rhodium Dinuclear Complex Strongly Bound to Filled dz2 Complexes by Unbridged Pt-metal Bonds Toward Heterometallic-Extended Metal Atom Chains Reviewed International journal
Kazuhiro Uemura, Yuya Ikeda, Atsushi Takamori, Tomoyuki Takeyama, Satoshi Iwatsuki
Chemistry - A European Journal 29 e202204057 2023.3
Joint Work
Authorship：Last author
Abstract: Heterometallic extended metal atom chains (EMACs) aligned with three types of metal were rationally synthesized by forming unbridged metal-metal bonds based on the interactions between highest occupied and lowest unoccupied molecular orbitals at the dz2 orbital. These chains form pentanuclear structures aligned as Rh-Pt-M-Pt-Rh with relatively large formation constants of 5.0×10^13 M^-2 for M = Pt and 6.3×10^11 M-2 for M = Pd, while retaining their backbones in solution. In the case of M = Cu, the original Cu(+2) atoms were reduced to Cu(+1) during the synthetic process. Cu(+1) has an unprecedented trigonal bipyramidal coordination geometry. The reported synthesis based on asymmetrical dinuclear complexes provides a guideline for the synthesis of hetero-EMACs to allow several analogs through judicious combinations realized by tuning the number of metal nuclei and metal species.
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Detailed Reaction Mechanism of Bis-(o-Aminomethylphenylboronic Acid)-based Receptors with Various Length Methylene-chain Linkers with D-Glucose Reviewed
Yuki Ohno, Rei Tanaka, Yota Suzuki, Tomoaki Sugaya, Satoshi Iwatsuki, Masahiko Inamo, Koji Ishihara
ChemistrySelect 7 e202200603 2022.8
Joint Work
The detailed reaction mechanisms of several bis-(o-aminomethylphenylboronic acid)-based receptors, linked with methylene chains of different lengths (i. e., DBAn (n=2, 3, and 4) having 2n methylene groups), with D-glucose were kinetically investigated in methanolic aqueous solutions. The pKa measurements showed that the two boronic acid moieties in DBAn were equivalent and had no electronic interaction between them. DBA2 reacted with D-glucose to form a 1:1 product, in which two boronic acid moieties in one molecule of DBA2 were bound to two reactive sites in one molecule of D-glucose. DBA3 and DBA4 reacted with D-glucose to form a 1:2 product, in which the two boronic acid moieties in one molecule of DBA3 or DBA4 were bound to two molecules of D-glucose simultaneously through one reactive site. Thus, in the recognition of D-glucose, the distance between the two boronic acid moieties in DBAn was optimal for n=2 and too long for n=3 or 4.
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Synthesis and characterization of a uranyl(VI) complex with 2,6-pyridine-bis(methylaminophenolato) and its ligand-centred aerobic oxidation mechanism to a diimino derivative Reviewed
Tomoyuki Takeyama, Satoshi Iwatsuki, Satoru Tsushima, Koichiro Takao
Dalton Transactions 51 6576 - 6586 2022.5
Joint Work
A uranyl(VI) complex with 2,6-bis(3,5-di-tert-butyl-o-phenolateaminomethyl)pyridine (UO2(tBu-pdaop), 1) was synthesized and thoroughly characterized by 1H NMR, IR, elemental analysis, and single-crystal XRD. Right after the dissolution of complex 1 in pyridine or DMSO, the solution was pale red, whereas it gradually turned to dark purple under an ambient atmosphere. 1H NMR spectra at the initial and final states suggested that both of the two aminomethyl groups in 1 were converted to azomethine ones through aerobic oxidation. Indeed, a uranyl(VI) complex with 2,6-bis(3,5-di-tert-butyl-o-phenolateiminomethyl) pyridine (UO2(tBu-pdiop), 2) was obtained from the concentrated solution once the reaction was completed, and was characterized by IR, and single-crystal XRD. Kinetic analyses as well as mechanistic studies based on quantum chemical calculations suggested that hydrogen atom transfer from one of the amino groups in complex 1 to nearby O2 initiates the stepwise oxidation processes to finally afford 2. The present findings demonstrate the novel reactivity of a uranyl(VI) complex, and provide new insights to construct thermally-driven molecular conversion systems by a UO2^2+ complex catalyst.
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Preparation of Tricationic Tris(pyridylpalladium(II)) Metallacyclophane as an Anion Receptor Reviewed International journal
Hiroshi Danjo, Kohei Asai, Tomoya Tanaka, Daiki Ono, Masatoshi Kawahata, Satoshi Iwatsuki
Chemical Communications 58 2196 - 2199 2022.2
Joint Work
Authorship：Last author
A tricationic tris(pyridylpalladium(II)) metallacyclophane was prepared from 3,5-dibromopyridine by a successive treatment with tetrakis(triphenylphosphine)palladium(0), diphosphine, and silver salt. Single-crystal X-ray diffraction analysis revealed that the metallacyclophane incorporated one of three counter anions into its hole-shaped cavity to form multidentate C–H---anion interactions. Solution-phase 1H NMR experiments in DMSO-d6 indicated that the metallacyclophane exhibited selective binding behavior toward nitrate, tetrafluoroborate, p-toluenesulfonate, perchlorate, and hydrogen sulfate ions, whereas the hexafluoroantimonate ion exhibited only weak interaction toward the metallacyclophane. This anion recognition behavior was further demonstrated by an extraction experiment of water-soluble sulfonate dyes.
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Colorimetric and fluorometric determination of boron using β-diketone–BF2 compounds containing catechol moiety Reviewed
Yukika Sobue, Ikumi Imanishi, Tomoaki Sugaya, Satoshi Iwatsuki, Msahiko Inamo, Koji Ishihara
Talanta Open 4 100076 2021.12
Joint Work
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Solid State Characterization of One- and Two-Electron Oxidized CuII-salen Complexes with para-Substituents: Geometric Structure-Magnetic Property Relationship Reviewed
Tomoyuki Takeyama, Takashi Suzuki, Misa Kikuchi, Misato Kobayashi, Hiromi Oshita, Kyohei Kawashima, Seiji Mori, Hitoshi Abe, Norihisa Hoshino, Satoshi Iwatsuki, Yuichi Shimazaki
European Journal of Inorganic Chemistry 2021 4133 - 4145 2021.10
Joint Work
Authorship：Corresponding author
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Structural Chemistry and Stimuli-Responsive Phase Transition of N,N’‑Dialkylimidazolium Nonafluorobutanesulfonate Ionic Liquids Reviewed
Tomoyuki Takeyama, Yuuki Inoue, Kenji Chayama, Satoshi Iwatsuki, Koichiro Takao
Crystal Growth & Design 21 617 - 624 2021.1
Joint Work
Authorship：Corresponding author
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Decomposition and Isomerization Mechanisms of Head-to-Head α-Pyridonato-Bridged Ethylenediamineplatinum(II) Binuclear Complex, [Pt2(en)2(C5H4NO)2]2+, in Aqueous Solution Reviewed
Yuuki Ito, Kohei Yamashima, Shintaro Arai, Makoto Takahashi, Tomohiro Ito, Satoshi Iwatsuki, Koji Ishihara, Kazuko Matsumoto
Inorganica Chimica Acta 513 119934 2020.8
Joint Work
Authorship：Corresponding author
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Kinetics and mechanisms for inorganic and organometallic reactions of bis(amidato)-bridged cis-diammineplatinum(III) binuclear complexes: A review Reviewed
Satoshi Iwatsuki, Koji Ishihara, Kazuko Matsumoto
Inorganica Chimica Acta 512 119888 2020.7
Joint Work
Authorship：Lead author, Corresponding author
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Benzyl alcohol oxidation mechanisms by one- and two-electron oxidized species of Cu(II)-salen complexes with para-R-substituents, [Cu(R-salen)]n+ (R = MeO, MeS; n = 1, 2) Reviewed
Tomoyuki Takeyama, Misato Kobayashi, Misa Kikuchi, Takashi Ogura, Yuichi Shimazaki, Satoshi Iwatsuki
Inorganica Chimica Acta 511 119848 2020.7
Joint Work
Authorship：Corresponding author
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Reactivity of Boronic Acids toward Catechols in Aqueous Solution Reviewed
Yota Suzuki, Daisuke Kusuyama, Tomoaki Sugaya, Satoshi Iwatsuki, Masahiko Inamo, Hideo D. Takagi, Koji Ishihara
The Journal of Organic Chemistry 85 5255 - 5264 2020.4
Joint Work
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A Tetrakisquinoline Analog of Calcium Indicator Quin2 for Fluorescence Detection of Cd2+ Reviewed
Yuji Mikata, Minori Kaneda, Marin Tanaka, Satoshi Iwatsuki, Hideo Konno, Arimasa Matsumoto
European Journal of Inorganic Chemistry 2020 757 - 763 2020.3
Joint Work
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Thermosensitive gels incorporating cyclic monoazatetrathioether units for the selective extraction of class b metal ions Reviewed
Kenji Chayama, Takumi Hirooka, Satoshi Iwatsuki
Journal of Inclusion Phenomena and Macrocyclic Chemistry 94 211 - 218 2019.6
Joint Work
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Detailed Reaction Mechanisms of 4-Pyridylboronic Acid and (N-Methyl)-4-Pyridinium Boronic Acid with D-Sorbitol in Aqueous Solution Reviewed
Daisuke Kusuyama, Yuta Samukawa, Tomoaki Sugaya, Satoshi Iwatsuki, Masahiko Inamo, Hideo D. Takagi, Koji Ishihara
ChemistrySelect 4 4944 - 4951 2019.5
Joint Work
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Methoxy-substituted tetrakisquinoline analogs of EGTA and BAPTA for fluorescent detection of Cd2+ Reviewed
Yuji Mikata, Minori Kaneda, Hideo Konno, Arimasa Matsumoto, Shin-ichiro Sato, Masaya Kawamura, Satoshi Iwatsuki
Dalton Transactions 48 3840 - 3852 2019.4
Joint Work
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Axial ligand substitution reactions of head-to-head α-pyridonato-bridged Pt(III) binuclear complexes bearing various equatorial ligands with chloride ion and olefin Reviewed
Shintaro Kusuhara, Kaori Kojima, Yota Suzuki, Yuki Morita, Tomoaki Sugaya, Satoshi Iwatsuki, Koji Ishihara, Kazuko Matsumoto
Journal of Molecular Liquids 262 556 - 564 2018.4
Joint Work
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Co-extraction and Concentration of Dyes into the Ionic Liquid Formed in an Aqueous Solution Reviewed
Kenji Chayama, Nobuhiko Ooi, Jun Kawamura, Mari Toyama, Satoshi Iwatsuki
The 21st International Solvent Extraction Conference (ISEC 2017 proceedings) 2017.11
Joint Work
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Axial-Ligand Substitution Reactions of a Head-to-Head Pivalamidato-Bridged Pt(III) Binuclear Complex Bearing Equatorial Bromide Ligands: A Mechanistic Study Reviewed
Takaaki Terada, Yu Kamezaki, Ryota Nakamura, Tomoaki Sugaya, Satoshi Iwatsuki, Koji Ishihara, Kazuko Matsumoto
Inorganica Chimica Acta 467 391 - 399 2017.9
Joint Work