Article
Chemistry, Multidisciplinary
Maia E. Czaikowski, Andrew J. McNeece, Jan-Niklas Boyn, Kate A. Jesse, Sophie W. Anferov, Alexander S. Filatov, David A. Mazziotti, John S. Anderson
Summary: Copper plays a crucial role in oxidative catalysis, with metal ligand cooperativity facilitating oxidation reactions. A Cu(II)-superoxo complex is generated by activating O₂, which then participates in various oxidation reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Inorganic & Nuclear
Jessica K. Bilyj, Nicole V. Silajew, Paul V. Bernhardt
Summary: The tetradentate N2S2 Schiff base ligands show versatile chelating behavior for copper and stabilize high oxidation states. The Ni coordination chemistry of these ligands leads to a variety of products, including dinuclear Ni-II complexes derived from radical homocoupling reactions. These complexes are redox active and exhibit new electronic transitions in spectroelectrochemistry.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Multidisciplinary
Yubin M. Kwon, Yuri Lee, Anna K. Schmautz, Timothy A. Jackson, Dong Wang
Summary: The recent focus on developing high-valent non-oxo-metal complexes has proven effective in studying their rich chemistry. In this study, a formal mononuclear Ni(IV)-nitrate complex was obtained and its geometric and electronic structures, bonding interactions, and spectroscopic properties were analyzed.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Multidisciplinary Sciences
Yuchao Chai, Bin Qin, Bonan Li, Weili Dai, Guangjun Wu, Naijia Guan, Landong Li
Summary: This study reports a method for selectively hydrogenating carbon dioxide to methanol using renewable hydrogen sources, which is both environmentally friendly and carbon neutral. By designing faujasite-encaged mononuclear Cu centers, stable methanol production and selectivity were achieved. This work provides a clear example of structure-activity relationship in catalysis and highlights the advantages of zeolite catalysis in complex chemical transformations.
NATIONAL SCIENCE REVIEW
(2023)
Article
Biochemistry & Molecular Biology
Xinzhe Zhong, Caitlin J. Bouchey, Evanta Kabir, William B. Tolman
Summary: By reacting copper-superoxide complexes with dicopper(I) complexes using different ligands, metastable intermediates with (peroxo)dicopper moieties were formed instead of the desired (peroxo)tricopper model under reaction conditions. The structures of these intermediates were proposed to be mu-eta(1): eta(2)-peroxo based on resonance Raman data and consideration of structural preferences for LCuX species.
JOURNAL OF INORGANIC BIOCHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Lukas Lohmeyer, Elisabeth Kaifer, Hans-Joerg Himmel
Summary: This study investigates the redox properties of cobalt complexes with redox-active bisguanidine ligands, and fine-tuning of the electronic structure is achieved through systematic modifications at the ligand units. The first observation of redox isomerism for cobalt complexes with redox-active guanidine ligands is reported.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Williamson N. Oloo, Miklos Szavuly, Jozsef Kaizer, Lawrence Que
Summary: This study describes a substrate oxidation reaction catalyzed by [Fe-II(IndH)(CH3CN)(3)](ClO4)(2) with H2O2, involving a spectroscopically characterized intermediate capable of olefin epoxidation and alkane hydroxylation. The research identified a direct nucleophilic attack of the substrate carbonyl group by the peroxo species. Additionally, the study found that the high-valent iron-oxo oxidant derived from O-O bond cleavage of the peroxo intermediate contributes to the oxidative reactivities associated with nonheme diiron enzymes.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Williamson N. Oloo, Miklos Szavuly, Jozsef Kaizer, Lawrence Que
Summary: This study elucidates the substrate oxidations catalyzed by [Fe-II(IndH)(CH3CN)(3)](ClO4)(2) with H2O2, resulting in the formation of a spectroscopically characterized (mu-oxo)(mu-1,2-peroxo)diiron(III) intermediate capable of various oxidative reactions including epoxidation and hydroxylation.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
David Vesseur, Karinne Miqueu, Didier Bourissou
Summary: A mono-substituted Au(I) carbene was synthesized by reacting HC(N-2)(Dmp) (Dmp = 2,6-dimesitylphenyl) with an (o-carboranyl)-diphosphine AuNTf2 complex. It exhibited stability up to about 10 degrees C and its structure was determined using NMR spectroscopy. Density functional theory calculations revealed that the chelating P<^>P ligand enhanced Au -> C-carb backdonation, while the Dmp substituent provided kinetic stabilization without altering the electronic structure of the carbene complex.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Masahiro Kouno, Naoto Kuwamura, Nobuto Yoshinari, Tatsuhiro Kojima, Malcolm A. Halcrow, Kohei Yamagami, Akira Sekiyama, Takumi Konno
Summary: A thermally stable trinuclear complex with an octahedral Ni-III center surrounded by thiolato donors was synthesized, isolated, and structurally characterized. The complex showed reversible distortion on dehydration/rehydration in the solid state. The one-electron oxidized and reduced species of the complex were also obtained and characterized.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Rakesh Kumar, Ayushi Awasthi, Sikha Gupta, Raju Eerlapally, Apparao Draksharapu
Summary: In this study, a synthetic Ru-III-OCl species was reported as a structural mimic of haloperoxidase enzymes. This species can persist for a certain period of time at room temperature and perform oxygen atom transfer and hydrogen atom abstraction to organic substrates.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Pablo Rios, Rocio Martin-de la Calle, Pietro Vidossich, Francisco Jose Fernandez-de-Cordova, Agusti Lledos, Salvador Conejero
Summary: A reversible carbon-boron bond formation has been observed in the reaction between a coordinatively unsaturated Pt(ii) complex and tricoordinated boranes, leading to the formation of several intermediate complexes. Computational methods suggest that the kinetic formation of carbon-boron coupling products is under kinetic control, while the platinum boryl species resulting from competitive C-H bond coupling are thermodynamically more stable. These findings provide valuable insights into productive carbon-boron coupling reactions at transition metal centers.
Article
Chemistry, Inorganic & Nuclear
Lena Steuer, Elisabeth Kaifer, Hans-Joerg Himmel
Summary: This study focused on the analysis of metal-guanidine bonding in dinuclear transition metal complexes with redox-active tetrakisguanidine ligands. Results showed the peculiarity of copper-guanidine bonding with a high pi-bond contribution to the metal-guanidine bonding.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Multidisciplinary
V. Mahesh Krishnan, Dimitar Y. Shopov, Caitlin J. Bouchey, Wilson D. Bailey, Riffat Parveen, Bess Vlaisavljevich, William B. Tolman
Summary: By modulating the properties of ligands, Cu(III) complexes bearing an oxygen-based auxiliary ligand were successfully stabilized and characterized for the first time, showing enhanced stability and slower reactivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Han Vinh Huynh, Hong Lee Ong, Kausani Ghatak
Summary: The preference for the formation of mono- versus dinuclear mixed carbene/thiolato complexes of Pd-II has been studied. It was found that mononuclear complexes are formed when the sulfur and carbon donors are exclusively cis to each other, while their trans arrangement preferably leads to dinuclear complexes with mu(2)-bridging thiolato ligands. The increased electron density in the latter case cannot be sufficiently compensated by one Pd-II center alone and leads to the formation of dinuclear species with bridging thiolato ligands.
DALTON TRANSACTIONS
(2021)
Article
Physics, Atomic, Molecular & Chemical
Taiki Shibata, Satoru Yamamoto, Shigeaki Nakazawa, Elham Hosseini Lapasar, Kenji Sugisaki, Koji Maruyama, Kazuo Toyota, Daisuke Shiomi, Kazunobu Sato, Takeji Takui
Summary: Quantum state control is crucial in advanced quantum technology, with molecular open shell entities serving as a testbed for implementing quantum control technology. The control of molecular spin qubits is important for quantum computers, where interactions between different spins play a key role. Indirect control via hyperfine interactions has the advantage of reducing unnecessary interactions with the environment, and optimizing experimental conditions is essential for achieving high-fidelity quantum gates.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Chemistry, Multidisciplinary
Tasuku Kumagai, Shuichi Suzuki, Yuki Kanzaki, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Rika Tanaka, Keiji Okada, Masatoshi Kozaki
Summary: We have designed and synthesized a new compound with a similar electronic structure to trimethylenemethane. Crystal structure analysis reveals that the dihedral angle between the two radical moieties is very small due to steric effects. The coplanarity of the radicals leads to a strong ferromagnetic interaction.
Article
Chemistry, Multidisciplinary
Tsuyoshi Murata, Noriaki Asakura, Ryotaro Tsuji, Yuki Kanzaki, Kazunobu Sato, Takeji Takui, Yasushi Morita
Summary: A new stable organic compound was synthesized, and porous organosiloxanes were prepared through the condensation of silyl groups. The compound exhibited unique characteristics in both solution and solid states. Additionally, the organosiloxanes demonstrated reversible redox ability.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Inorganic & Nuclear
Ryu Tanimoto, Tomoyuki Wada, Keiji Okada, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Shuichi Suzuki, Takeshi Naota, Masatoshi Kozaki
Summary: This study investigates the magnetic behavior of a gadolinium(III) complex at different temperatures and finds that the magnetic susceptibility changes with temperature, which can be explained by the structural change of the ligand.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Koki Horii, Ryohei Kishi, Masayoshi Nakano, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Akihito Konishi, Makoto Yasuda
Summary: Bis-periazulene and its derivatives exhibit unique electronic structures and energy states, providing potential applications in extended π-conjugated systems.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Akihiro Shimizu, Tetsuya Morikoshi, Kenji Sugisaki, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Ryo Shintani
Summary: This study describes the design, synthesis, and isolation of a Kekule hydrocarbon with a triplet ground state. The triplet ground state was confirmed through ESR experiments, and the structure and fundamental physical properties were also revealed. The key aspect of the molecular design is the decrease in bonding interaction in the singlet state through aromatic stabilization of benzene rings and the increase of exchange interaction of unpaired electrons, which is favorable for the triplet state. These findings contribute to the development of hydrocarbon-based organic magnetic materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Kenji Sugisaki, Kazuo Toyota, Kazunobu Sato, Daisuke Shiomi, Takeji Takui
Summary: In this study, numerical simulations of adiabatic state preparation (ASP) were performed to generate ground state wave functions for molecules with strongly correlated electrons. Practical conditions for close-to-exact correlated wave function preparation were proposed. The effect of nonlinear scheduling functions and ASP with broken-symmetry wave functions were examined, contributing to practical applications of quantum computing in quantum chemistry.
COMMUNICATIONS CHEMISTRY
(2022)
Article
Physics, Atomic, Molecular & Chemical
Isao Suetake, Kazunobu Sato, Tomoaki Sugishita, Yuichi Mishima, Toshiki Takei, Toshimichi Fujiwara, Risa Mutoh, Akira Shinohara, Takeji Takui, Makoto Miyata, Hironobu Hojo, Toshiaki Arata
Summary: Heterochromatin protein 1 (HP1) is an epigenetic reader with two conserved domains, the chromoshadow domain (CSD) and chromodomain (CD). The hinge region (HR) connects the CD and CSD. The N- and C-tails as well as the HR are estimated to be disordered. EPR spectra showed site-specific slower dynamics in the disordered regions, with the HR being influenced by the N-tail and the C-terminal region of HR interacting with the C-tail. Surprisingly, DNA did not affect the spectra, but restricted CD and CSD in HP1 alpha.
APPLIED MAGNETIC RESONANCE
(2023)
Article
Physics, Atomic, Molecular & Chemical
Kazunobu Sato, Rei Hirao, Satoru Yamamoto, Konstantin L. Ivanov, Takeji Takui
Summary: This article presents methods for optimizing frequency sweeps to achieve fast adiabatic inversion in ESR spectroscopy. The optimization is performed either by exploiting constant adiabaticity chirps or using the gradient ascent pulse engineering (GRAPE) method, which evaluates the & UDelta;(t) profiles to minimize the chirp duration. Arbitrary waveform generator-based ESR (AWG-ESR) allows for the application of versatile MW-shaped pulses and control of the spin system dynamics. Spin dynamics for spin inversion by the shaped pulses were observed. Comparison of different frequency sweeps indicates a significant reduction in the duration of adiabatic sweeps for both homogeneous and inhomogeneously broadened ESR signals.
APPLIED MAGNETIC RESONANCE
(2023)
Editorial Material
Physics, Atomic, Molecular & Chemical
Kazunobu Sato, Elena Bagryanskaya, Marco Affronte, Stephen Hill
APPLIED MAGNETIC RESONANCE
(2023)
Article
Chemistry, Physical
Kenji Sugisaki, Hiroyuki Wakimoto, Kazuo Toyota, Kazunobu Sato, Daisuke Shiomi, Takeji Takui
Summary: In this paper, we extend the Bayesian phase difference estimation (BPDE) algorithm to calculate the energy difference of two molecular geometries directly. By applying the BPDE algorithm with numerical energy gradients based on the finite-difference method, we demonstrate the feasibility of geometry optimization of one-dimensional molecules on a quantum computer. Simulations of various molecular systems validate the effectiveness of the proposed method.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Shohei Koyama, Kazunobu Sato, Masahiro Yamashita, Ryota Sakamoto, Hiroaki Iguchi
Summary: The study investigates the magnetic relaxation of BTI-xy radical anions without pi-stacking interaction, which leads to slow magnetization relaxation reported for the first time in organic radicals. The relaxation times in a solution state highlight the significance of spin interaction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Keiga Toshima, Tetsu Sato, Yoji Horii, Kazunobu Sato, Kenji Sugisaki, B. K. Breedlove, Shinya Takaishi, Zhao-Yang Li, Masahiro Yamashita
Summary: This study reports the slow magnetic relaxation behavior and T-2 values of three low-spin Ni(III) based complexes, suggesting their potential as molecule-based spin qubits under magnetically diluted conditions.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Akihiro Shimizu, Masaaki Hayashida, Yuta Ochi, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Ryo Shintani
Summary: A zwitterionic open-shell singlet diradical composed of electron-donating anion and electron-accepting cation was synthesized and showed near-infrared absorption. The diradical has a small energy gap between the ground singlet and thermally-excited triplet states (Delta E-ST), which can be changed by solvents.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Shinobu Arikawa, Akihiro Shimizu, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Hikaru Sotome, Hiroshi Miyasaka, Masahito Murai, Shigehiro Yamaguchi, Ryo Shintani
Summary: A kinetically-stabilized nitrogen-doped triangulene cation derivative with a triplet ground state that exhibits near-infrared emission has been synthesized and isolated. The triplet ground state with a large singlet-triplet energy gap was experimentally confirmed by magnetic measurements. The nitrogen-doped triangulene cation derivative is highly stable even in solution under air and exhibits near-infrared absorption and emission due to the broken alternancy symmetry of triangulene.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
