Article
Chemistry, Organic
Naoyuki Hisano, Takeharu Haino
Summary: The host-guest complexation between a bisporphyrin cleft and electron-deficient guest molecules was studied. The X-ray crystal structures showed that the guest molecules were located within the cleft and formed pi-pi stacking interactions. Binding constants and thermodynamic parameters were determined using isothermal titration calorimetry. Two types of enthalpy-entropy compensation effects were observed based on the guest's movement within the cleft. Chiral guest encapsulation induced bisignate circular dichroism.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Hua Zhong, Sixun Jiang, Lei Ao, Fan Wang, Feng Wang
Summary: Phosphorescent host-guest systems, which have intriguing properties and diverse applications, have attracted considerable attention. In this study, a functionalized metallotweezer receptor capable of noncovalent complexation with platinum(II) terpyridine compounds was designed and synthesized. The resulting heterometallic host-guest complexes exhibited enhanced phosphorescent emission and could assemble into nanospheres. When a specific complementary guest was used, the system showed phosphorescent solvatochromic behaviors.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Susana Ibanez, Eduardo Peris
Summary: Two different metallotweezers were used as hosts for a series of planar aromatic guests. The binding strength and models of the two metallotweezers differed due to their structural differences.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Sangmin Lee, Thi Vo, Sharon C. Glotzer
Summary: In this study, hard truncated triangular bipyramids self-assemble into seven different colloidal clathrate crystals, consisting of cages that are either empty or occupied by guest particles. Monte Carlo simulations reveal that the crystallization occurs through the compartmentalization of entropy between low- and high-entropy subsystems for the host and guest particles. The researchers also use entropic bonding theory to design host-guest colloidal clathrates with explicit interparticle attraction for experimental realization.
Article
Chemistry, Physical
Binh Minh Nguyen, Markus Schmid, Johann Kirsch, Albin Cakaj, Wolfgang Bruetting
Summary: The orientation mechanism of nonpolar dyes in various conditions is studied. It is found that the shape anisotropy and temperature ratio are key factors controlling dye alignment. It is also noted that caution must be exercised when using mixed cohost systems with different glass transition temperatures, as the emitter orientation may not follow the effective glass transition temperature of the mixed host.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Tao Liu, Zitong Meng, Yihang Zhou, Teng Wang, Kang Lv
Summary: The detailed mechanisms of Ni-catalyzed ligand-controlled cyclization/cross-coupling of o-bromobenzenesulfonyl acrylamide with trifluoromethyl alkene were investigated by DFT calculations. The computational results revealed that the reduction state of the complex determines the progress of the cyclization reaction and identified the most favorable catalytic cycle mechanism.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Hyejin Kwon, Carson J. Bruns
Summary: Researchers have discovered and characterized a family of all-hydrocarbon, all-p-conjugated [n]cycloparaphenylene-PAH host-guest complexes. They have built a theoretical framework to select these complexes and predict their stabilities. This research offers new opportunities for bespoke PAH separation or remediation materials.
Article
Chemistry, Multidisciplinary
Zheng Zhou, Yikun Zhu, Zheng Wei, John Bergner, Christian Neiss, Susanne Doloczki, Andreas Goerling, Milan Kivala, Marina A. Petrukhina
Summary: The study found that the chemical reduction of octaphenyltetrabenzocyclooctatetraene framework can readily produce the corresponding tetra-anion instead of the expected aromatic dianion. X-ray crystallography shows that the highly contorted tetra-anion is stabilized by the coordination of two internally bound Li+ ions, while two external cations are solvent separated. Density-functional theory calculations suggest that the formation of the highly charged tetra-reduced carbanion is stabilized through Li+ coordination under the applied experimental conditions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Medicinal
Xiao Liu, Lei Zheng, Chu Qin, Yang Li, John Z. H. Zhang, Zhaoxi Sun
Summary: End-point free-energy methods are widely recognized as a tool with certain screening power in pharmaceutical research. However, there is currently a lack of large-scale benchmarks in host-guest complexes to support the screening power of these methods. In this study, a large dataset of 154 host-guest pairs is constructed, and extensive end-point sampling is performed using various free-energy techniques to estimate the free energy.
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2023)
Article
Biochemistry & Molecular Biology
Aysun Degirmenci, Rana Sanyal, Amitav Sanyal
Summary: Polymeric surface coatings capable of integrating functional molecules and ligands can be fabricated through modular design using host-guest chemistry. The copolymers containing Ada moieties, DEG units, and silyloxy groups were synthesized and used to modify silicon/glass surfaces. Coating surfaces using these polymers allowed for efficient and robust functionalization with various functional molecules and bioactive ligands. The polymeric coating also demonstrated selective binding capabilities and the potential for cell attachment and proliferation. This approach offers an attractive method for engineering functional interfaces with biomedical applications.
Article
Nanoscience & Nanotechnology
Mohammad R. Momeni, Zeyu Zhang, David Dell'Angelo, Farnaz A. Shakib
Summary: The thermodynamics and kinetics of O-2 adsorption on 2D metal-organic frameworks were studied using quantum mechanical calculations. It was found that the redox-active linkers in Co-3(HTTP)(2) play a crucial role in chemisorption of O-2, leading to changes in conductive behavior under oxygen-rich conditions. The results provide insights into the impact of electroactive guest molecules on the structure and conductivity of 2D MOFs and related materials.
Article
Polymer Science
Mansur S. Miftakhov, Seda A. Torosyan, Fanuza A. Gimalova, Sergey L. Khursan, Zoya F. Nuriakhmetova, Elena V. Shchurik, Olga. A. Kraevaya, Aleksandr F. Shestakov, Pavel A. Troshin
Summary: This article introduces the synthesis of methylene-separated bis(thieno[3,2-b]pyrroles) and thieno[3,2-b]pyrrolopyrroles polymeric materials, which were found to be insoluble in organic solvents. The synthesized polymers were tested as cathode materials in potassium-ion batteries and displayed promising electrochemical performances.
Article
Chemistry, Physical
Valya Nikolova, Anita Velinova, Stefan Dobrev, Nikoleta Kircheva, Silvia Angelova, Todor Dudev
Summary: The interactions between neutral/protonated mitoxantrone and cucurbit[n]uril (n = 7, 8) host systems were analyzed using density functional theory calculations. It was found that stable inclusion complexes can form between doubly and quadruply charged mitoxantrone molecules and CB[7] or CB[8] in a water solvent. Both CB[7] and CB[8] show properties that are useful for drug delivery.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Review
Chemistry, Inorganic & Nuclear
Xi Yang, Di Yuan, Jinhong Hou, Adam C. Sedgwick, Suying Xu, Tony D. James, Leyu Wang
Summary: The field of supramolecular chemistry has rapidly expanded and become highly influential in various areas like biomedicine, energy materials, catalysis, and sensing. The combination of host/guest chemistry with functional inorganic nanoparticles has led to many new applications in drug delivery, bioimaging, and sensing. Recent progress in the development of organic/inorganic supramolecular nano-systems incorporating host/guest chemistry has been summarized, highlighting their applications in drug delivery, biological imaging, and sensing.
COORDINATION CHEMISTRY REVIEWS
(2021)
Article
Chemistry, Multidisciplinary
Thomas A. Sobiech, Yulong Zhong, Daniel P. Miller, Jillian K. McGrath, Christina T. Scalzo, Morgan C. Redington, Eva Zurek, Bing Gong
Summary: The article presents experimental results on the binding of a rigid aromatic oligoamide macrocycle with DABCO-based cationic guests in highly polar DMF, demonstrating strong positive cooperativity. The unusually strong positive cooperativity mechanism is verified through various experimental methods. This host-guest system provides a tunable platform for studying molecular interactions and constructing stable supramolecular assemblies due to its exceptional positive cooperativity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Md Rafikul Islam, Tohru Nishinaga, Kazunori Hirabayashi, Toshio Shimizu, Ken-ichi Sugiura
Summary: This study focused on the oxidation reactions of 1,2-diarylbenzenes to induce intramolecular C-C bond formation. The substrates were prepared using stepwise Suzuki-Miyaura coupling reactions to introduce different groups on the ortho-positions of benzene. The oxidation reaction with FeCl3 resulted in the formation of two C-C bonds within the molecules, with theoretical calculations suggesting the importance of spin densities for this bond formation. The pi-expanded molecules obtained also showed shifts in absorption spectra.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Hirokazu Miyoshi, Ryosuke Sugiura, Ryohei Kishi, Sarah N. Spisak, Zheng Wei, Atsuya Muranaka, Masanobu Uchiyama, Nagao Kobayashi, Shreyam Chatterjee, Yutaka Ie, Ichiro Hisaki, Marina A. Petrukhina, Tohru Nishinaga, Masayoshi Nakano, Yoshito Tobe
Summary: The dianion and dication of tetramesityl-substituted tetracyclopentatetraphenylene, a circulene consisting of alternating five- and six-membered rings, have been successfully synthesized by reduction and oxidation methods. The theoretical prediction of annulene-within-an-annulene structures has been experimentally proven, with electronic configurations supported by MCD spectra. The distribution of electron charges inside and outside the ions has also been confirmed through experimental analyses.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Tomohiko Nishiuchi, Daisuke Ishii, Seito Aibara, Hiroyasu Sato, Takashi Kubo
Summary: In this study, a highly stable TAntM radical was successfully synthesized using a TIPS-ethynyl group, which effectively suppresses the reactivity of the radical. Chemical modification of the radical can be performed at room temperature, making it a versatile strategy for constructing unique spin-labelled molecules.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Tomohiko Nishiuchi, Hikaru Sotome, Kazuto Shimizu, Hiroshi Miyasaka, Takashi Kubo
Summary: In this study, 1,2,3-tri(9-anthryl)benzene derivatives containing three radially arranged anthracenes in a pi-cluster were synthesized using Negishi coupling. The unique electronic properties and excited-state dynamic behavior of these derivatives, such as exciton localization/delocalization, were investigated.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Risa Honda, Mizuki Takasugi, Kazunori Hirabayashi, Tohru Nishinaga, Toshio Shimizu, Ken-Ichi Sugiura
Summary: This study investigated the bromination reaction of dinaphtho[2,1-b:1 ',2 '-d]furan (DNF), and confirmed the regioselective introduction of bromine atoms at the 5- and 9-positions of DNF. The steric effect of the bulky bromine atoms was found to propagate through the peripheral hydrogens and/or DNF skeleton, resulting in the observed large helicity. Theoretical studies supported the proposed remote steric effect.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Tomohiko Nishiuchi, Seito Aibara, Takuya Yamakado, Ryo Kimura, Shohei Saito, Hiroyasu Sato, Takashi Kubo
Summary: This article investigates the characteristics of overcrowded ethylenes composed of 10-methyleneanthrone and two bulky aromatic rings. The crystals of these ethylenes exhibit various colors in different solvents due to their unique conformational features. Experimental studies reveal the relationships between the colors and the twist angles, fold angles, and dihedral angles of the ethylenes. Moreover, these conformations can be influenced by mechanical, pressure, and thermal stimuli.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Tomohiko Nishiuchi, Seito Aibara, Hiroyasu Sato, Takashi Kubo
Summary: Researchers have reported the preparation of AQD-containing π-extended hydrocarbons, which can stabilize singlet and triplet spin biradicaloids by incorporating nonplanar aromatic groups, enabling control of spin states through conformational changes.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Yoichi Tanabe, Yoshikazu Ito, Katsuaki Sugawara, Samuel Jeong, Tatsuhiko Ohto, Tomohiko Nishiuchi, Naoaki Kawada, Shojiro Kimura, Christopher Florencio Aleman, Takashi Takahashi, Motoko Kotani, Mingwei Chen
Summary: This study systematically investigated the electronic properties of N-doped 3D graphene using an electric-double-layer transistor method. It was found that Urbach-tail-like localized states exist around the neutral point of N-doped 3D graphene with background metallic transport channels. The dual nature of electronic states, resulting from the synergistic effect of N dopants and 3D curvature of graphene, can explain the high electrocatalytic activity, enhanced molecular adsorption, and light absorption of N-doped 3D graphene.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Tomohiko Nishiuchi, Shino Takeuchi, Yuta Makihara, Ryo Kimura, Shohei Saito, Hiroyasu Sato, Takashi Kubo
Summary: A Negishi coupling based synthesis of 1,2,4,5-tetra(9-anthryl)benzene derivatives with X-shaped molecular structures is described. X-ray crystallographic analysis reveals that the two-dimensional highly ordered packing structure of the unsubstituted derivative is a result of intermolecular interactions between anthracene units. Photoirradiation of the unsubstituted derivative promotes intramolecular [4+4] photocycloaddition reactions, leading to the formation of a crystalline polycyclic product featuring a unique long carbon-carbon single bond. Additionally, charge-transfer complexes exhibiting near-infrared absorption and emission are formed by co-crystallization with electron acceptor molecules.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2022)
Article
Chemistry, Organic
Tomohiko Nishiuchi, Yuta Makihara, Ryohei Kishi, Hiroyasu Sato, Takashi Kubo
Summary: Substances containing two pi-congested aromatic systems have attracted much attention in synthetic studies and exploration of unique properties. This study investigated the stacked antiaromaticity of highly pi-congested anthracene dimers and found relatively weak antiaromatic character.
JOURNAL OF PHYSICAL ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yusuke Kawabe, Yoshikazu Ito, Yuta Hori, Suresh Kukunuri, Fumiya Shiokawa, Tomohiko Nishiuchi, Samuel Jeong, Kosuke Katagiri, Zeyu Xi, Zhikai Li, Yasuteru Shigeta, Yasufumi Takahashi
Summary: Understanding the catalytic mechanism of highly active two-dimensional electrocatalysts is crucial to their rational design. This study reveals the element dependence of the reactivity of two-dimensional metal dichalcogenide sheets for electrocatalytic CO2 reduction. Tin(IV) disulfide (SnS2) sheets exhibited a Faradaic efficiency of 63.3% for formic acid, while molybdenum(IV) disulfide (MoS2) sheets showed an efficiency close to 0%. The active sites of SnS2 were identified as terraces and edges, and its effective utilization of the entire surface area enables efficient catalytic reactions. This finding provides a direction for material research in two-dimensional electrocatalysts for energy-efficient chemical production and other energy devices.
Article
Chemistry, Multidisciplinary
Samuel Jeong, Tatsuhiko Ohto, Tomohiko Nishiuchi, Yuki Nagata, Jun-ichi Fujita, Yoshikazu Ito
Summary: To realize advanced fuel-cell technology, proton exchange membranes with high proton conductivity and low crossover of fuel molecules are required. In this study, a simple yet powerful method is proposed to optimize the crossover-conductivity relationship by using sulfanilic-functionalized holey graphenes supported by a Nafion membrane. The results show significant reduction in crossover and proton conductivity, indicating potential for application in advanced fuel cells that use methanol and formic acid as chemical fuels.
Article
Chemistry, Multidisciplinary
Tomohiko Nishiuchi, Kazuyuki Uchida, Takashi Kubo
Summary: We synthesized and characterized hexabenzo[5.6.7]quinarene, a compound composed of anthraquinodimethane (AQD) core with fluorenyl and dibenzosuberenyl end-caps. The compound exists as a stable folded form due to strong intramolecular spin-spin interaction through the central AQD unit. By oxidation and reduction of the dication, a twisted triplet species is obtained, which thermally reverts to the folded form. This is a spin-switching system using a combination of chemical oxidation/reduction and thermal stimulation.
CHEMICAL COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Tohru Nishinaga, Kazuki Matsuo, Tomoya Koizumi, Ken-ichi Sugiura
Summary: A conjugated mixed tetramer consisting of EDOT and ProDOT dimers was introduced on the gold nanoparticle surface via a ligand exchange reaction. The resulting film showed improved conductivity after chemical oxidation and iodine doping, suggesting the formation of stable radical cations and the presence of an effective conduction path.
MATERIALS ADVANCES
(2022)
Article
Chemistry, Multidisciplinary
Tomohiko Nishiuchi, Hikaru Sotome, Kazuto Shimizu, Hiroshi Miyasaka, Takashi Kubo
Summary: This study reported the synthesis of 1,2,3-tri(9-anthryl)benzene derivatives with unique electronic properties via Negishi coupling. In the crystalline state, interactions between anthracene units facilitated the formation of a two-dimensional packing structure. Understanding the excited-state dynamic behavior revealed insights into exciton localization/delocalization processes.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)