Article
Chemistry, Multidisciplinary
Md Emdadul Hoque, Ranjana Bisht, Anju Unnikrishnan, Sayan Dey, Mirja Md Mahamudul Hassan, Saikat Guria, Rama Nand Rai, Raghavan B. Sunoj, Buddhadeb Chattopadhyay
Summary: A method of para-selective borylation of aromatic amides is described using a newly designed ligand framework (defa), which shows excellent selectivity and reactivity for the para position. This method can contribute to the development of new catalytic systems and the synthesis of para-functionalized compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Yajun Wang, Wenju Chang, Shengmeng Qin, Han Ang, Jiawei Ma, Shuo Lu, Yong Liang
Summary: Herein, we report a tunable meta- and para-selective C-H borylation of aryl sulfonyl compounds enabled by computationally designed ligands and iridium catalyst. This method is capable of accommodating a broad range of substrates under mild reaction conditions and can achieve gram-scale preparation with low iridium catalyst loading. Our method provides a general solution to installing functional groups at either meta- or para-position of aryl sulfones and aryl sulfonamides with good to excellent selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Kotaro Yamashita, Kota Sato, Yutaka Tanji, Jun-ya Hasegawa, Tetsuaki Fujihara
Summary: Dirhodium complexes with bulky carboxylate ligands were synthesized and characterized. The steric bulk of carboxylate ligands has an impact on the selectivity in Rh-catalyzed intramolecular reactions: Rh catalysts with bulky carboxylate ligands preferentially produced five-membered ring products via insertion into a carbon-hydrogen bond, while conventional Rh catalysts obtained six-membered ring products via insertion of a carbon-carbon double bond.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Zheng-Jun Wang, Xiangyang Chen, Lei Wu, Jonathan J. Wong, Yong Liang, Yue Zhao, Kendall N. Houk, Zhuangzhi Shi
Summary: The research presents a general strategy for site-selective C-H borylation of pyrroles using BBr3 directed by pivaloyl groups, without the need for any metal catalysts. The reaction is influenced by chelation and electronic effects, leading to diverse products with high positional selectivity and downstream transformation capabilities. DFT calculations confirm the preferred positional selectivity of this reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Hao Deng, Marco Bengsch, Nico Tchorz, Constanze N. Neumann
Summary: This article introduces a novel method for fine-tuning phosphine ligands, which enables diversification of phosphine compounds by introducing different substituents into previously inaccessible positions. Compared to existing methods, this approach overcomes the limitations of phosphorus-directed reactions.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Review
Chemistry, Multidisciplinary
Mengna Cao, Hujun Xie
Summary: This review discusses the current research status and future development direction of ligand-controlled reaction selectivity in nickel- and palladium-catalyzed cross-coupling reactions.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Physical
Matthew E. Grundy, Lia Sotorrios, Milan Kumar Bisai, Kang Yuan, Stuart A. Macgregor, Michael J. Ingleson
Summary: [(NacNac)Zn(DMT)][B(C6F5)4], 1, was synthesized and demonstrated as an efficient catalyst for the C-H borylation of (hetero)arenes using catecholborane. Computational studies revealed a plausible mechanism involving displacement of DMT by CatBH and subsequent steps including dehydrocoupling and displacement of CatBAr. The research also provided insight into a possible decomposition pathway of the catalyst involving boron to zinc hydride transfer.
Article
Chemistry, Physical
Matthew E. Grundy, Lia Sotorrios, Milan Kumar Bisai, Kang Yuan, Stuart A. Macgregor, Michael J. Ingleson
Summary: This article reports the synthesis of (NacNac)Zn(DMT) complex via two different routes and its use as a catalyst for C-H borylation. Computational studies elucidated the reaction mechanism and revealed the influence of the electronic and steric parameters of the base on the catalyst's performance.
Article
Chemistry, Physical
Koji Kubota, Daiyo Miura, Takumi Takeuchi, Shun Osaki, Hajime Ito
Summary: The study introduces a novel catalytic enantioselective nucleophilic borylation reaction of ketimines, leading to the efficient synthesis of optically active alpha-amino tertiary boronates with high enantioselectivity. The products can be further converted into peptidylboronic acid derivatives that are difficult to synthesize by other methods. Density functional theory calculations suggest that noncovalent interactions play a crucial role in determining the enantioselectivity of this reaction.
Article
Chemistry, Physical
Dai-Yu Li, Rui-Mu Yu, Jin-Ping Li, Deng-Feng Yang, Qi Pang, Hong-Liang Li
Summary: This article describes an improved para-selective C(sp(2))-H borylation of anisole derivatives. The selective borylation is likely to be influenced by the change in electron density on the aromatic ring when a Lewis acid coordinates with an anisole substrate. In addition, the use of a sterically hindered bipyridyl ligand in the reaction also promotes para-selectivity. This strategy has demonstrated a significant improvement in the ratio of para-borylated products, with the reaction taking place at milder temperatures and most substrates displaying moderate to good site-selectivity.
Article
Chemistry, Physical
Idoia Ruiz Larramendi, Inigo Lozano, Marina Enterria, Rosalia Cid, Maria Echeverria, Sergio Rodriguez Pena, Javier Carrasco, Hegoi Manzano, Garikoitz Beobide, Imanol Landa-Medrano, Teofilo Rojo, Nagore Ortiz-Vitoriano
Summary: The use of bulky cations TBA(+) and Cs+ in Na-O-2 batteries as electrolyte additives helps stabilize sodium superoxide and promote larger NaO2 cube growth, with Cs+ showing a stronger effect. Both additives increase discharge capacity, with Cs+ providing a 50% enhancement. TBA(+) improves superoxide stabilization, but steric hindrance limits its interaction compared to Cs+. The presence of Cs+ leads to a more stable solid-electrolyte interphase, enhancing the cycle life of Na-O-2 batteries.
ADVANCED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Mei Zhang, Hongli Wu, Jinjin Yang, Genping Huang
Summary: The recently developed iridium-catalyzed C(sp(3))-H borylation with the 2,2'-dipyridylarylmethane ligand provides a highly efficient catalytic system for alkane borylation, with the active catalyst species being the borylated cyclometalated Ir(III) diboryl complex. The superior activity of the ligand is attributed to the F-B noncovalent interactions and trans influence, enabling a one-stone-two-birds strategy to enhance catalytic activity.
Article
Chemistry, Physical
Jing Ma, Haonan Fan, Biaobiao Hao, Yan Jiang, Libo Wang, Xun Wang, Jingyi Zhang, Tao Jiang
Summary: The catalytic performance of Cr(III) based catalysts in ethylene oligomerization can be significantly affected by the asymmetric alkylphosphanyl carbon-bridged diphosphine Ph2PC = CPR1(R2)-type L1-L5 ligand. Different precatalysts exhibit variations in catalytic activity, product selectivity, and thermal stability.
JOURNAL OF CATALYSIS
(2022)
Review
Chemistry, Organic
Jiang Wang, Shi Zhuangzhi
Summary: Organoboron compounds serve as important building blocks to generate molecular diversity, and strategies enabling the conversion of readily available hydrocarbons into these compounds through C-H borylation are highly appealing. While significant progress has been made in ortho-selective C-H borylation, achieving meta-/para-selectivity remains challenging. This review provides a comprehensive overview of iridium-catalyzed meta-/para-selective aromatic C-H borylation, categorized into directed and non-directed approaches.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Jiahang Lv, Xue-Jun Zhang, Minyan Wang, Yue Zhao, Zhuangzhi Shi
Summary: The study developed a metal-free P(III)-directed phosphine C-H borylation method, mediated by BBr3, to synthesize products containing both phosphorus and boron. The metal-free strategy features low cost, practicality, and environmental friendliness.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Spectroscopy
Kenya Tanaka, Taishi Nishihara, Akira Takakura, Yasutomo Segawa, Kazunari Matsuda, Yuhei Miyauchi
Summary: In this study, polarized Raman spectroscopy was used to investigate the topological semimetal Co3Sn2S2. The results revealed that the Raman signals at low and high wave numbers are related to phonon modes with different symmetries. The high wave number A1g mode showed an asymmetric peak feature, indicating a Fano resonance with the continuous electronic background. These findings not only serve as fingerprints for verifying the crystal structure of Co3Sn2S2, but also highlight the importance of Raman spectroscopy as an effective tool to study low energy excitations and their interactions in this material.
JOURNAL OF RAMAN SPECTROSCOPY
(2023)
Article
Biochemistry & Molecular Biology
Ayaka Ueda, Yusuke Aihara, Shinya Sato, Keiko Kano, Emi Mishiro-Sato, Hiroyuki Kitano, Ayato Sato, Kazuhiro J. Fujimoto, Takeshi Yanai, Kazuma Amaike, Toshinori Kinoshita, Kenichiro Itami
Summary: This study discovered 2,6-dihalopurines as a new inhibitor of stomatal opening and investigated its mechanism. Biological assays suggested that the pathway related to plasma membrane H+-ATPase phosphorylation may be involved. Through affinity-based pull down assay and molecular dynamics simulation, Leucine-rich repeat extensin proteins (LRXs), LRX3, LRX4, LRX5, and RALF were identified as target protein candidates for 2,6-dihalopurines. The mechanism of stomatal movement related to LRXs-RALF is an unexplored pathway, and further studies may uncover new signaling pathways and regulatory factors in stomatal movement.
ACS CHEMICAL BIOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Ayaka Ueda, Kazuma Amaike, Yoko Shirotani, Hideto Ito, Robin Warstat, Jae-Hoon Choi, Hirokazu Kawagishi, Kenichiro Itami
Summary: Imidazole-4-carboxamide (ICA), a type of fairy chemical (FCs) causing fairy ring phenomena, exhibits plant growth inhibitory activity. FCs have the potential to be a new family of plant hormones as they are endogenous in all tested plant species and regulate plant growth. This study focuses on the synthesis of ICA derivatives and evaluation of their activity in rice. Surprisingly, several compounds show unexpected elongation activity in root and shoot growth.
CANADIAN JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Kou P. Kawahara, Hideto Ito, Kenichiro Itami
Summary: We have developed a sulfur-embedding annulative pi-extension (thia-APEX) reaction to efficiently construct a sulfur-embedding cationic hexagonal aromatic ring called thiopyrylium onto unfunctionalized aromatics in a one-step process. The key of the thia-APEX reaction lies in the utilization of S-imidated ortho-arenoyl arenethiols, enabling easy synthesis of diverse pi-extended thiopyryliums. The synthesized thiopyryliums exhibit various absorption and emission properties across the visible light to NIR region, depending on minor structural variations.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Wataru Matsuoka, Kou P. Kawahara, Hideto Ito, David Sarlah, Kenichiro Itami
Summary: In this study, we successfully achieved a late-stage pi-extension of rubrene using dearomative annulative pi-extension (DAPEX), leading to the generation of rubrene derivatives with an extended aromatic core. These pi-extended rubrenes displayed a marked red shift in absorption and emission spectra, indicating the extension of the rubrene's aromatic pi-system both structurally and electronically. Furthermore, organic field-effect transistor devices using two-side pi-extended rubrene were fabricated, demonstrating the potential utility of these compounds in organic electronics with a comparable carrier mobility to rubrene thin-film transistors.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Nobushige Kai, Hideya Kono, Akiko Yagi, Kenichiro Itami
Summary: A novel structurally constrained nanobelt, methylene bridged [6]cyclo-2,6-naphthylene ([6]MCN), was synthesized via the nickel-mediated intramolecular aryl-aryl coupling of a triflated prism[6]arene. The structural and electronic properties of [6]MCN were characterized using NMR studies and photophysical measurements. In contrast to methylene-bridged [6]cycloparaphenylene, our previously synthesized benzene-based analogue, [6]MCN exhibited low strain energy (77.4 kcalmiddotmol(-1)) and bright fluorescence (Phi = 0.20).
Article
Chemistry, Multidisciplinary
Takahiro Ono, Kazuhito V. Tabata, Yuki Goto, Yutaro Saito, Hiroaki Suga, Hiroyuki Noji, Jumpei Morimoto, Shinsuke Sando
Summary: Cyclic peptides that passively penetrate cell membranes are being actively researched in drug discovery. Common methods like PAMPA and Caco-2 assay have limitations in accurately measuring their permeability. A new lipid bilayer permeability assay was developed for label-free measurements of cyclic peptide permeability.
Article
Chemistry, Multidisciplinary
Eiki Tomita, Masahiro Kojima, Yuki Nagashima, Ken Tanaka, Haruki Sugiyama, Yasutomo Segawa, Atsushi Furukawa, Katsumi Maenaka, Satoshi Maeda, Tatsuhiko Yoshino, Shigeki Matsunaga
Summary: The synthesis, characterization, and catalytic performance of an iridium(III) catalyst with an electron-deficient cyclopentadienyl ligand were reported. The catalyst was synthesized by complexation of a precursor of the electron-deficient ligand with an iridium compound, followed by oxidation, desilylation and removal of another ligand. The electron-deficient catalyst enabled C-H amidation reactions assisted by a weakly coordinating directing group.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Medicinal
Aya Ogata, Takashi Yamada, Saori Hattori, Hiroshi Ikenuma, Junichiro Abe, Mari Tada, Masanori Ichise, Masaaki Suzuki, Kengo Ito, Takashi Kato, Kazuma Amaike, Tsuyoshi Hirota, Akiyoshi Kakita, Kenichiro Itami, Yasuyuki Kimura
Summary: Positron emission tomography (PET) is a powerful imaging tool for early detection of Alzheimer's disease (AD) that has been developed to target beta-amyloid and tau protein aggregates. This study focuses on the development of a new PET ligand targeting protein kinase CK2, which is known to be altered in AD brains.
BIOORGANIC & MEDICINAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Hideya Kono, Yuanming Li, Guglielmo Monaco, Riccardo Zanasi, Francesco F. Summa, Lawrence T. Scott, Akiko Yagi, Kenichiro Itami
Summary: Cycloparaphenylenes (CPPs) and carbon nanobelts (CNBs) are cyclic molecular nanocarbons with unique properties derived from rigid, strained, and cyclic p-conjugated systems. The synthesis of various sizes of CPPs and CNBs has allowed for the investigation of their size-dependent properties and use in various applications. The synthesis, size-dependent properties, and paratropic belt currents of methylene-bridged [n]cycloparaphenylenes ([n]MCPP, n = 6, 8, 10) were reported and studied.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Kanna Fujishiro, Yuta Morinaka, Yohei Ono, Tsuyoshi Tanaka, Lawrence T. Scott, Hideto Ito, Kenichiro Itami
Summary: In this study, a lithium(0)-mediated mechanochemical anionic cyclodehydrogenation reaction was developed for the first time. The reaction could be easily performed using a conventional and easy-to-handle lithium(0) wire at room temperature, even under air, and achieved high yields in a short time. The study also comprehensively investigated the applicability and practicality of the protocol, as well as limitations, through computational studies and nuclear magnetic resonance analysis. Furthermore, novel nanographenes, including quinterrylene, were successfully synthesized using this method.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Takaku Yoshihara, Hiroki Shudo, Akiko Yagi, Kenichiro Itami
Summary: Peripheral structural modifications of arenes have a significant impact on their optoelectronic properties, molecular assembly, and stability. Annulation with an adamantane scaffold is a simple yet powerful modification strategy that leads to unique effects, such as high solubility and enhanced conjugation. The oxidation of adamantane-annulated perylenes produces cationic species with extended emission in the near-infrared region, potentially contributing to the development of groundbreaking pi-materials and novel nanocarbon materials.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Yusuke Aihara, Bumpei Maeda, Kanna Goto, Koji Takahashi, Mika Nomoto, Shigeo Toh, Wenxiu Ye, Yosuke Toda, Mami Uchida, Eri Asai, Yasuomi Tada, Kenichiro Itami, Ayato Sato, Kei Murakami, Toshinori Kinoshita
Summary: The authors identify BITC as a stomatal opening inhibitor that suppresses PM H+-ATPase phosphorylation. They develop BITC derivatives with higher inhibitory activity that increase drought tolerance in plants.
NATURE COMMUNICATIONS
(2023)
Article
Plant Sciences
Yuki Nakashima, Yuka Kobayashi, Mizuki Murao, Rika Kato, Hitoshi Endo, Asuka Higo, Rie Iwasaki, Mikiko Kojima, Yumiko Takebayashi, Ayato Sato, Mika Nomoto, Hitoshi Sakakibara, Yasuomi Tada, Kenichiro Itami, Seisuke Kimura, Shinya Hagihara, Keiko U. U. Torii, Naoyuki Uchida
Summary: A compound called PLU has been discovered to induce the formation of pluripotent callus in plants without the need for external hormone application. The PLU-induced callus expresses marker genes associated with pluripotency acquisition. This study provides a new approach to manipulate and investigate the induction of plant pluripotency.
FRONTIERS IN PLANT SCIENCE
(2023)
Article
Chemistry, Organic
Kou P. Kawahara, Hideto Ito, Kenichiro Itami
Summary: This paper describes the synthesis of pi-extended thianthrene derivatives from unfunctionalized aromatics using thia-APEX reactions. The reaction involves the fusion of new benzodithiine arms to the aromatic substrates in one step, resulting in the formation of pi-extended thianthrenes with yields ranging from 21% to 87%. The reaction requires equimolar amounts of the aromatic substrates and S-diimidated 1,2-arenedithiols, along with a catalytic amount of TfOH, and the synthesized pi-extended thianthrenes were characterized for their solid state packing structures and photophysical properties.
ORGANIC CHEMISTRY FRONTIERS
(2023)