著者

八木 政行

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.57, pp.67-74, 2011-05-31 (Released:2011-08-31)

参考文献数

84

---

Artificial photosynthesis is expected as one of promising clean energy-providing systems in future. Development of an efficient catalyst for water oxidation to evolve O2 is a key task to yield a breakthrough for construction of an artificial photosynthetic device. Recently, significant progress has been reported in development of the molecular catalysts for water oxidation based on manganese, ruthenium and iridium complexes. The molecular aspects of the catalysts in chemical, electrochemical, and photo- or photoelectro-driven water oxidation were reviewed to provide hints to design an efficient catalyst. This review will mainly cover the related progress in the last 5 or 6 years.

著者

Leroy Cronin

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.78, pp.11-17, 2021-11-30 (Released:2021-12-28)

参考文献数

23

被引用文献数

1

---

The mechanism that controls the self-assembly of complex polyoxometalate inorganic clusters in solution is a challenge because the clusters can contain anywhere from 6 to 368 metal ions in a single molecule and are commonly assembled under ʻone-potʼ reaction conditions. Furthermore, harnessing the ʻself-assemblyʼ processes allows synthesis on a length-scale and with a degree of complexity which is not easily accessed by more traditional ʻstep-wiseʼ synthesis routes. This class of molecules are important as they can be thought of as ʻmolecular metal oxidesʼ and rival the size of proteins yet are based upon simple MOx units (where M is Mo, W, V and sometimes Nb and x can be 4, 5, 6 or 7). Here we review the structures of the molybdenum-based clusters and then show how it is possible to not only control the architectures but explore the mechanism of formation invoking mechanisms that are normally found in biological systems. We describe how a simple inorganic salt can spontaneously form ʻinformation-richʼ, autocatalytic sets of replicating inorganic molecules that work via molecular recognition based on the [PMo12O40]3–, {PMo12} Keggin ion, and [Mo36O112(H2O)16]8–, {Mo36} cluster. These small clusters are involved in an autocatalytic network, where the assembly of gigantic molybdenum blue wheels [Mo154O462H14(H2O)70]14– {Mo154}, [Mo132O372(H2O)72(CH3CO2)30]42–, {Mo132} ball containing 154 and 132 molybdenum clusters are templated by the smaller clusters which are themselves able to catalyze their own formation. Finally, We introduce assembly theory and show how assembly theory can be used to describe the constraints that need to be present to facilitate the assembly of the large clusters and explain how information theoretic arguments might be useful for designing highly functional and unsymmetrical inorganic molecules.

著者

相田 卓三

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.53, pp.17-23, 2009-05-31 (Released:2009-10-01)

参考文献数

20

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This review article gives an overview of our recent discovery that a Gemini-shaped hexa-peri-hexabenzocoronene (HBC) amphiphile (1) and its derivatives undergo highly controlled self-assembly to form a new family of nanotubes that may be called ‘graphite’ nanotubes. Compound 1 possesses hydrophilic triethylene glycol (TEG) chains on one side of the HBC core and hydrophobic dodecyl side chains on the other. The nanotubes are characterized by uniform diameter and wall thickness, a large aspect ratio, and designable inner and outer surfaces. Furthermore, they possess a helical chirality. In fact, under certain conditions, a coiled assembly, which is a kinetically preferred product, is formed temporarily and then transforms, on annealing, into a tubular assembly. Furthermore, HBC derivatives bearing a stereogenic center can form coiled and tubular assemblies with a one-handed helical chirality. Analogous to compound 1, HBC amphiphiles carrying functional groups at the TEG termini self-assemble in a highly controlled manner, affording surface-functional nanotubes. As one of the ideal designs for photovoltaic materials with a nanometric size regime, photoconductive nanotubes with a coaxial configuration of the donor/acceptor heterojunction is highlighted.

著者

山田 泰之 田中 健太郎

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.62, pp.12-22, 2013-11-30 (Released:2014-03-20)

参考文献数

62

被引用文献数

1

---

In this review, we focus on the integrated assemblies of metal complexes and their functional emergence generated by the synergy effects of π-π stacking interaction and metal complexation. Programmable construction of integrated molecular assemblies is the best measure for bringing out the emergent functions which can be evolved from the intermolecular communications of functional molecular components. Combination of π-π stacking interaction and metal complexation allows not only to reinforce the mutual interactions but also to generate the emergent intermolecular communications. This review introduces the recent studies including the synergy effects on electrical, magnetic, catalytic and molecular recognition functions in soft, crystalline and single molecular materials.

著者

大久保 將史

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.82, pp.29-41, 2023-11-30 (Released:2023-12-26)

参考文献数

63

---

A net-zero society needs integration of a large amount of renewable energy to a power grid while ensuring the quality of electricity. As the intermittent power from the renewables should be load-leveled using low-cost and high-power 1 MWh-scale stationary batteries, sodium-ion batteries that are comprised of abundant elements have attracted recent research interest. One of the most promising positive electrode materials for sodium-ion batteries is a family of Prussian blues (PB) and Prussian blue analogues (PBA), which delivers a large capacity of > 150 mAh/g at a high operating voltage of approximately 3.5 V vs. Na/Na+, meeting performance criteria for large-scale stationary batteries. However, for their commercialization, especially in Japan, further data accumulation including cycle stability, safety, and life cycle assessment is necessary. This review summarizes recent research and development of the PB and PBA electrodes for sodium-ion batteries.

著者

沈 建仁

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.72, pp.3-14, 2018-11-30 (Released:2019-04-01)

参考文献数

62

被引用文献数

1 1

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Photosystem II (PSII) is a huge membrane-protein complex catalyzing light-induced electron transfer and water oxidation reactions, leading to the conversion of light energy into chemical energy and the evolution of molecular oxygen, two products indispensable for sustaining almost all life forms on the earth. This account describes the structure of PSII with the focus on that of the catalytic center for water oxidation, a Mn4CaO5-cluster embedded in the protein matrix of PSII, revealed by conventional highresolution X-ray crystallography and femtosecond X-ray free electron laser (XFEL) crystallography. Latest results on the structural changes of the Mn4CaO5-cluster during the water oxidation reaction cycle obtained by the femtosecond XFEL crystallography are also described. Based on these results as well as those obtained with other approaches, the mechanism of water oxidation and oxygen evolution is discussed. Other functions of PSII such as proton release pathways and light energy absorption and transfer are also discussed briefly.

著者

杉本 学

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.54, pp.52-67, 2009-11-30 (Released:2010-04-16)

参考文献数

116

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Theoretical and computational studies on metal-complex photosensitizers, photo-induced electron transfer, and electric characteristics of dye-sensitized solar cells (DSSC) are reviewed as a typical example of interacting molecular systems. For the photosensitizers, we focus on Ru(II) polypyridyl complexes. Electronic structure studies using the density functional theory are summarized with a particular interest on electronic factors giving appreciable influence on their UV/Vis absorption spectra. For photoinduced electron transfer, which has been suggested to be the most important process in DSSC, introduced are three quantum models each of which is useful for understanding either qualitative or quantitative aspects of the electronic process. For DSSC characteristics, some models of carrier transport are explained. From the materials science viewpoint, it is evident that coordination chemistry plays an important role for developing such an interacting molecular system where “variety of combination” and “structural hierarchy” are its characteristics. In this review, the current status and future challenges of theoretical and computational studies are pointed out with an emphasis on importance of theory-experiment collaborations.

著者

藤田 誠

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.57, pp.13-29, 2011-05-31 (Released:2011-08-31)

参考文献数

122

被引用文献数

2 2

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Molecular self-assembly has recently undergone on explosive development, making possible the synthesis of many fascinating and complex structures using only relatively simple procedures. Over the last two decades, we have been showing that the simple combination of palladium's square planer geometry (a 90 degree coordination angle) with pyridine-based bridging ligands gives rise to the quantitative self-assembly of nano-sized, discrete organic frameworks. Representative and early examples in this field include square molecules (1990), linked-ring molecules (1994), cages (1995), tubes (1999), capsules (1999), and spheres (2004) that are self-assembled from simple and small components. By networking the discreet frameworks, we have also developed porous coordination networks (1994). In this article, we will disclose the structure of these self-assemblies as well as the chemistry of self-assembled “space” created in the void of the assemblies, where new chemical and physical properties of enclosed molecules are exhibited.

著者

大木 靖弘

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.66, pp.26-30, 2015-11-30 (Released:2016-03-04)

参考文献数

27

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Nirtogenases are a class of enzymes that catalyze the reduction of N2 to NH3 under ambient conditions in the presence of protons and electrons. The active site of the most prevalent nitrogense is called as the FeMo-cofactor, which is often designated as the M-cluster. It consists of one molybdenum, seven irons, and several sulfur atoms, and represents the most complex metal-sulfur cluster in biology. Some homologues containing vanadium or iron in place of molybdenum exist in alternative nitrogenases, while a precursor of FeMo-cofactor was also identified as an all-iron homologue. Recent crystallographic and biochemical studies on nitrogenases uncovered some important clues about the structurefunction relationship of the nitrogenase active sites, such as the precise structure of the FeMo-cofactor, unique catalytic functions of the FeMo-cofactor and its homologues, and the detailedmechanistic insights in the nitrogen fixation. Transition-metal mediated conversion of small molecules that contain triple bonds has been of interest to the community of coordination chemistry, and this contribution introduces some important progresses in the nitrogenase chemistry/biochemistry made in recent years.

著者

井頭 麻子 藤原 隆司 堀 顕子

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

no.58, pp.55-59, 2011-11

著者

坪村 太郎 佃 俊明 松本 健司

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.52, pp.29-42, 2008-11-30 (Released:2009-02-13)

参考文献数

100

被引用文献数

8 9

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The study in the area of luminescent d10 complexes has been developing rapidly. The metals with d10 electronic configuration have a closed d-shell, therefore the nature of the complexes are quite different from regular transition metal complexes. The complexes show a diversity of the electronic excited states. This paper reviews the characteristic nature of the d10 metal complexes with interesting examples. Copper(I), silver(I), gold(I), nickel(0),palladium(0) and platinum(0) complexes are discussed. Luminescent copper(I) complexes are classified into two groups; the first includes the complexes bearing halogen ligands, and the second have no halogen ligands. In the second group, the complexes with phosphine and diimine type ligands are mainly discussed. As for the silver(I) and gold(I) complexes, multinuclear complexes are mostly described. For the palladium(0) and platinum(0) complexes, although a small number of works have been published so far, some interesting studies including our works have been described. In addition to the recent studies on the photophysical properties of the complexes, some applications are described in this review.

著者

桑田 繁樹

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.76, pp.21-30, 2020-11-30 (Released:2021-01-05)

参考文献数

70

---

Proton-responsive pincer-type ligands have been used as scaffolds to realize metal–ligand cooperative transformations. Unlike most of the ligands therein, 2,6-bis(pyrazol-3-yl)pyridines (3-bpp) ensure that two protic groups point to the remaining coordination site in the pincer plane. This article reviews the coordination chemistry of 3-bpp and related tridentate ligands with emphasis on the characteristics originating from the Brønsted acidity of the peripheral NH groups. Synthesis of 3-bpp complexes, which often associated with spontaneous deprotonation of the 3-bpp ligand and aggregation of the complex to give supramolecular structures, is first described. Deprotonation of the 3-bpp complexes along with the following reactivities is then discussed. Application of the 3-bpp complexes to catalytic reactions as well as materials exhibiting spin-crossover and fluorescence is also described. Finally, pincer-type complexes bearing protic N-heterocyclic carbene side arms are briefly mentioned as relevant molecules.

著者

杉本 直己

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.65, pp.23-29, 2015-05-31 (Released:2015-09-11)

参考文献数

15

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Nucleic acids can adopt many types of noncanonical structures such as a triple helix and a quadruplex depending on the sequence and solution conditions. Recently, we developed a molecular crowding system which is the cell mimicking system to investigate thermodynamic behaviors of nucleic acids in cell. As results of our researches, the molecular crowding stabilizes the quadruplex with Hoogsteen base pairs, while it destabilizes the duplex with Watson-Crick base pairs which is the canonical structure. In this review, based on the thermodynamic results of DNA and RNA under the crowding condition, regulation of transcription and translation by the quadruplex structure of nucleic acids and its stabilizers is described. It is possible that the polymerase and ribosome bound to the template DNA and RNA, respectively, may mimic the crowded conditions in which we have shown to stabilize the quadruplex. Our results presented in this review indicate that stable noncanonical structures regulate transcription and translation. The results further our understanding of the transcription and translation processes involving the noncanonical structures and may guide the design of transcription and translation regulating drugs.

著者

西林 仁昭

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.71, pp.49-55, 2018-05-31 (Released:2018-08-24)

参考文献数

22

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This paper describes our recent progress in catalytic nitrogen fixation by using transition metal-dinitrogen complexes as catalysts. Novel reaction systems for the catalytic transformation of molecular dinitrogen into ammonia and hydrazine undermild reaction conditions have been achieved by the molybdenum-, iron-, cobalt-, and vanadium-dinitrogen complexes as catalysts. New findings presented in this paper may provide a new approach to the development of economical nitrogen fixation in place of energy-consuming Haber-Bosch process.

著者

森迫 祥吾 山下 誠

出版者

錯体化学会

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.74, pp.29-45, 2019-11-30 (Released:2020-03-12)

参考文献数

100

被引用文献数

1

---

In this article, recent developments regarding the organometallic chemistry of boron-containing pincer ligands, especially in which a boron coordinated to transition metal center as an anionic σ-donor ligand, are reviewed. Boron-based pincer ligands can be subdivided into three main classes; diazaborole-, carborane-, and diarylboryl-ligand. All the papers relevant to such boron-based pincer ligands that have been published since 2009 are included in this review, which also summarizes applications of transitionmetal complexes bearing such boron-containing pincer ligands in catalytic and/or bond-cleavage reactions.

著者

中野 元裕

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.58, pp.6-19, 2011-11-30 (Released:2012-03-05)

参考文献数

75

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The octahedral manganese(III) complex, [MnIII(taa)] (H3taa = tris(1-(2-azolyl)-2-azabuten-4-yl)amine), has long been known as a rare example of (3d)4 spin-crossover system, having a steep spin-crossover phase transition at Tc = 48 K between a high-spin 5Eg and a low-spin 3T2g states. Since the high-spin state is obviously subject to the Jahn-Teller effect, the electronic states are coupled with lower-symmetry deformation modes lifting 5Eg orbital degeneracy in addition to a symmetrical breathing mode responsible for the spin crossover. This simultaneous involvement of two molecular bistabilities may afford a variety of condensed states (phases) due to competitive or cooperative interactions. The phase diagram and the phase transition behavior were thoroughly explored via several probes, including dielectric measurements, magnetization under pulsed high field, HF-EPR, and magnetic susceptibility measurements using high-pressure clamp cell. All the results were successfully interpreted in a unified fashion based on a four-state Ising-Potts model with mean-field approximation.

著者

François-Xavier Coudert

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.73, pp.15-23, 2019-05-31 (Released:2019-07-10)

参考文献数

94

被引用文献数

5

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Recent years have seen a large increase in the number of reported framework materials, including the nowadays-ubiquitous metal–organic frameworks (MOFs). Many of these materials show flexibility and stimuli-responsiveness, i.e. their structure can undergo changes of large amplitude in response to physical or chemical stimulation. We describe here a toolbox of theoretical approaches, developed in our group and others, to shed light into these materials’ properties. We focus on their behavior under mechanical constraints, temperature changes, adsorption of guest molecules, and exposure to light. By means of molecular simulation at varying scale, we can now probe, rationalize and predict the behavior of stimuli-responsive materials, producing a coherent description of soft porous crystals from the unit cell scale all the way to the behavior of the whole crystal. In particular, we have studied the impact of defects in soft porous crystals, and developed a methodology for the study of their disordered phases (presence of correlated disorder, MOF glasses, and liquid MOFs)

著者

久枝 良雄

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.54, pp.10-21, 2009-11-30 (Released:2010-04-16)

参考文献数

69

被引用文献数

6 6

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This account describes a current summary of our research on the development of bio-inspired catalysts with vitamin B12 enzyme functions for degradation of environmental pollutants. We have been interested in vitamin B12-dependent enzymes, involving the cobalt species as a catalytic center, and dealing with a hydrophobic vitamin B12, heptamethyl cobyrinate perchlorate, which has ester groups in place of the peripheral amide moieties of the naturally occurring vitamin B12. In order to construct a good catalytic system, we prepared various nanomaterials with vitamin B12 activities. For example, a vesicle-type artificial enzyme composed of peptide lipids and hydrophobic vitamin B12, a vitamin B12-ruthenium photo-sensitizer system, a vitamin B12-titanium dioxide hybrid catalyst and so on. These bio-inspired catalysts are very interesting from the viewpoint of green chemistry. 1,1-bis(4-chlorophenyl)- 2,2,2-trichloroethane (DDT) is characterized by a pronounced insecticidal property and has been used worldwide for the last several decades despite its known hazardous effects on human health and wildlife. Because of recent environmental concerns, there is pressing need for efficient methods for degradation of such chlorinated compounds accumulated in the soil. DDT was degradated effectively by the electrochemical method and the bio-inspired catalysts with vitamin B12 function. Such vitamin B12 derivatives also can apply the detoxification of inorganic arsenic by the methylation.

著者

山内 幸正

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.62, pp.26-28, 2013-11-30 (Released:2014-03-20)

参考文献数

11

被引用文献数

1 1

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In nature, hydrogenase enzymes catalyze H2 production from water with the turnover frequency (TOF) of 9000 s-1. In this context, studies on the water-splitting reactions with use of earth-abundant metal complexes have attracted great attention, and some nickel complexes have recently been reported to show efficient catalysis in hydrogen production. Dubois et al. demonstrated that a nickel(II) bis(diphosphine) complex with tertiary amines serves as an electrocatalyst for H2 production with the TOF of 106,000 s-1. The pendant amine was proposed to act as a proton relay promoting the nickel hydride formation together with H-H bond fixation, mimicking the reaction field of [FeFe] hydrogenase. In addition, visible-light-driven hydrogen production in the presence of the analogous complex is also promoted with 2700 turnover numbers (TONs) after 150 h, as reported by Holland et al. On the other hand, Eisenberg et al. showed that a biomimetic pyridinethiolate nickel(II) complex gives 5500 TONs over 40 h, employing the photocatalytic H2-evolving system. In the active form of the complex, coordinated pyridine is suggested to dissociate from nickel center to serve as a proton shuttle instead. These results indicate that a nickel(II) compound has considerable potential to become an alternative to platinum catalyst in the future.

著者

伊藤 肇 関 朋宏

出版者

Japan Society of Coordination Chemistry

雑誌

Bulletin of Japan Society of Coordination Chemistry (ISSN:18826954)

巻号頁・発行日

vol.62, pp.3-11, 2013-11-30 (Released:2014-03-20)

参考文献数

70

被引用文献数

1

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Aryl gold isocyanide complexes are found to have interesting photoluminescence properties in the solid state, being referred to as luminescence mechanochromism and molecular domino. A gold complex containing two gold atoms, {[pentafluorophenylgold]2(μ-1,4-diisocyanobenzene)}, shows significant change in its luminescence property when mechanical stimulus such as grinding or pressing is applied on its solid sample. This “luminescence mechanochromism” is most probably attributed to a ground state structure change from the microcrystalline to the amorphous state accompanied to the optical properties alternations. Different feature observed in phenyl(phenyl isocyanide)gold(I) complex is “molecular domino”, where even a small mechanical stimulus can trigger the structure change of the entire crystal. This spontaneous structure change proceeded in a single-crystal-to-single-crystal fashion with the drastic emission color alternation. These features enable sub-molecular-level structure investigation with single X-ray crystallographic analysis and visual observation of the phase transition under UV light irradiation during the mechano-induced phase change.