Article
Chemistry, Physical
Jiaojiao Song, Yixuan Yang, Shoujie Liu, Lei Li, Nan Yu, Yuteng Fan, Zhiming Chen, Long Kuai, Baoyou Geng
Summary: This study investigates the impact of dispersion and support on the activity of Pt in CO oxidation reaction, revealing that reducible TiO2 significantly influences Pt activity with lower apparent activation barriers, and that single-atom dispersion of Pt maximizes active sites.
Article
Chemistry, Multidisciplinary
Mohammad Ali Bodaghifard, Saeideh Shafi
Summary: A novel hybrid nanostructure (CoFe2O4@SiO2@PAF-IL) was investigated for catalyzing the synthesis of benzothiazole and benzimidazole derivatives, showing good yields and short reaction times. The nanomaterial offers solvent-free and environmentally-friendly conditions, and can be easily separated and reused with an external magnetic field.
JOURNAL OF THE IRANIAN CHEMICAL SOCIETY
(2021)
Article
Multidisciplinary Sciences
Majid Rouzifar, Sara Sobhani, Alireza Farrokhi, Jose Miguel Sansano
Summary: A sunlight-induced tandem air oxidation-condensation reaction using Co-isatin-Schiff-base-MIL-101(Fe) as a heterogeneous multifunctional bio-photocatalyst is reported for the efficient synthesis of benz-imidazoles/-oxazoles/-thiazoles and benzylidene malononitrile. This environmentally friendly process utilizes inexpensive catalyst, sunlight irradiation, air as an oxidant, and ethanol as a green solvent.
SCIENTIFIC REPORTS
(2023)
Article
Nanoscience & Nanotechnology
Jianwei Zheng, Liying Zhang, Yang Li, Hongbin Sun, Gang Zhang, Qi Sun
Summary: Core-shell nanocomposites with a catalytic metal-organic framework (MOF) shell are more effective and stable than bare MOF. The Fe3O4@SiO2@UiO-66 core-shell structure shows high catalytic ability and magnetic recyclability, maintaining high catalytic activity and stability over six cycles.
Article
Chemistry, Medicinal
Anja Bec, Livio Racane, Teo Tomic, Leentje Persoons, Dirk Daelemans, Mihailo Banjanac, Vedrana Radovanovic, Marijana Hranjec
Summary: The aim of this study was to synthesize novel benzazoles with amidino and 2-hydroxyphenyl substituents and explore their biological activity. New benzazoles were synthesized by condensation of 5-substituted salicylaldehydes and intermediates using previously developed procedures, and were tested for antibacterial and antiproliferative activity in vitro. The results showed that benzimidazole with a 2-imidazolinyl group 27 and benzothiazole with an unsubstituted amidine 48 exhibited the best antibacterial activity (minimum inhibitory concentration 8 μg/ml). Benzothiazole 53 was found to be the most potent compound in inhibiting the proliferation of various cancer cells (IC50: 1.2-2.0 μM). In conclusion, the most active compounds have been identified as lead compounds for further optimization to enhance their biological activity. The type of amidine moiety significantly influenced the biological activity, with benzothiazoles showing superior antiproliferative activity compared to benzimidazoles.
FUTURE MEDICINAL CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Valentina Rep Kaulic, Livio Racane, Marijana Leventic, Domagoj Subaric, Vesna Rastija, Ljubica Glavas-Obrovac, Silvana Raic-Malic
Summary: Syntheses of 6-halogen-substituted benzothiazoles and 6-amidino-substituted benzothiazoles were performed. The antiproliferative activity of the compounds was evaluated on tumor cell lines, and it was found that the amidino benzothiazoles exhibited stronger inhibitory activity compared to non-substituted and halogen-substituted benzothiazoles. Imidazolyl benzothiazoles showed nonselective activity, except for 36c which had a strong inhibitory effect on HuT78 cells without cytotoxicity on normal cells. Structural analogs containing the 1,2,3-triazole ring showed pronounced and selective activity against HuT78 cells. QSAR models elucidated the effects of the substituents at position 6 of benzazoles on the antiproliferative activity.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Physical
R. Arun, M. P. Athira, Sebastian Nybin Remello, Suja Haridas
Summary: In this study, sulfonic acid functionalized SBA-15 was synthesized by post-synthetic functionalization of mesoporous SBA-15. Physico-chemical characterization confirmed the successful incorporation of sulfonic acid moiety into the SBA-15 framework. A simple synthetic route for the synthesis of 2-aryl benzimidazoles and benzothiazoles using SBA-15-SO3H as a green heterogeneous catalyst at room temperature was investigated. It achieved 100% conversion and an isolated yield of 70-85%, while offering reaction under ambient conditions, a simple work-up procedure, good to excellent yield and easy product isolation, along with good recyclability.
REACTION KINETICS MECHANISMS AND CATALYSIS
(2023)
Article
Biochemistry & Molecular Biology
Livio Racane, Ivo Zlatar, Natasa Perin, Maja Cindric, Vedrana Radovanovic, Mihailo Banjanac, Suresh Shanmugam, Marijana Radic Stojkovic, Karmen Brajsa, Marijana Hranjec
Summary: Newly designed and synthesized compounds with benzimidazole/benzothiazole structures showed potential antitumor activity by inhibiting proliferation of human lung cancer cell lines. Benzothiazole derivatives exhibited higher activity compared to benzimidazole derivatives. Some compounds also demonstrated antimicrobial activity.
Review
Chemistry, Organic
Steeva Sunny, Stephy Elza John, Nagula Shankaraiah
Summary: The review summarizes the utilization of transition metal-catalyzed C-H bond activation for the functionalization of 2-aryl benzoazoles, contributing to the drug discovery process.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Zahra Dehbanipour, Ali Zarnegareyan
Summary: This study investigates the synthesis and characterization of a new heterogeneous catalyst, Pd(II)Cl2-BTP@MNPs, which is composed of palladium (II) 3,5-bis(2-benzothiazolyl)pyridine supported on magnetic nanoparticles. The catalyst shows excellent performance in the reaction between derivatives of benzyl alcohol with 1,2-phenylenediamine or 2-aminothiophenol, leading to the synthesis of benzothiazoles and benzimidazoles. Furthermore, the catalyst can be reused multiple times without significant loss of catalytic activity.
INORGANIC CHEMISTRY COMMUNICATIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Ke Li, Yu-Feng Liu, Xiao-Ling Lin, Guo-Ping Yang
Summary: The three new polyoxometalate-based metal-organic frameworks synthesized in this study demonstrate different multinuclear copper clusters and topological structures, serving as heterogeneous catalysts with high stability and excellent catalytic activity for the synthesis of nitrogen-heterocycle compounds.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Jiaming Hu, Mengjia Li, Jing Wan, Jinnan Sun, Hu Gao, Feng Zhang, Zhibing Zhang
Summary: A metal-free synthesis method for benzimidazole compounds is reported. NHPI is used as a nonmetallic catalyst, combined with molecular oxygen or air as the oxidant, for the synthesis of N-heterocycles. Flow microreactors under optimized conditions improve the reaction efficiency.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Physical
Heyan Jiang, Cuicui Zang, Hongmei Cheng, Bin Sun, Xue Gao
Summary: Porous borocarbonitride (P-BCN) with enhanced crystallinity and improved N-B pair exposure was prepared using a simple KCl-assisted molten salt strategy, enabling efficient heterogeneous photocatalytic synthesis of benzazoles. The improved photocatalytic performance is attributed to the enhancement in charge separation and transmission, as well as the promotion of superoxide radical generation and oxidation ability. This work presents a green and efficient synthetic strategy towards benzazoles and other fine chemicals through metal-free heterogeneous photocatalysis.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Organic
Sankaranarayanan Jayashree, Kalegowda Shivashankar
Summary: The recyclable sulfated copper oxide catalyst in acetonitrile was effective in synthesizing N-fused benzimidazolo/benzothiazolo pyrimidine derivatives from 2-aminobenzimidazole/2-aminobenzothiazole, phenyl acetylene, and benzaldehydes, providing a unified approach to assemble a wide variety of fused pyrmidines.
POLYCYCLIC AROMATIC COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Rakhi Katla, Ramesh Katla, Nelson Luis C. Domingues
Summary: In this study, a quick and eco-friendly method for synthesizing biologically active 2-substituted benzimidazoles and benzothiazoles was developed using Zn(L-Pro)(2) as a catalyst in ethanol at room temperature through an aerobic oxidative cyclization reaction involving o-phenylenediamine and 2-aminothiophenol with various substituted aldehydes.
Article
Chemistry, Multidisciplinary
Yuki Nakaya, Eigo Hayashida, Ruikun Shi, Ken-ichi Shimizu, Shinya Furukawa
Summary: The role of subsurface carbon and the synergistic effects of Au and KOAc in the acetoxylation of ethylene have been investigated. The presence of subsurface carbon in Pd-Au/SiO2 catalyst was found to enhance the catalytic performance in VAM synthesis. Experimental and theoretical analysis also suggests that the coupling reaction between acetate and ethylene is effectively promoted by the synergistic contributions of Au and interstitial carbon, inhibiting ethylene dehydrogenation and CO2 formation. These insights provide new possibilities for the design of catalysts with improved catalytic performance.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Hiroe Kubota, Shinya Mine, Takashi Toyao, Ken-ichi Shimizu
Summary: In this study, Ag-loaded Al2O3 catalysts with different alumina powders were prepared and their catalytic activities were investigated for the selective catalytic reduction (SCR) of NO by NH3 or C3H6. The results showed that the activity of the catalysts and the size of the Ag metal nanoparticles changed with different alumina supports. The molecular-level insights into the design of sintering-resistant Ag/Al2O3 catalysts for SCR were provided.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Lingcong Li, Ziyang Wu, Shinta Miyazaki, Takashi Toyao, Zen Maeno, Ken-ichi Shimizu
Summary: Continuous CO2 capture and reduction for CH4 production was investigated using a double reactor system over Al2O3-supported Ni-Ca dual functional materials in the presence of O2. A high Ca loading (Ni(10)-Ca(30)/Al2O3) was found to be necessary for reaction efficiency. The optimized dual functional material showed excellent performance and stability.
Article
Chemistry, Physical
Ningqiang Zhang, Shinta Miyazaki, Yucheng Qian, Yuan Jing, Takashi Toyao, Ken-ichi Shimizu
Summary: Kinetic analyses of Ce4+ <-> Ce3+ redox and CO2/H-2 formation for the unsteady-state water-gas shift (WGS) reaction are carried out on Cu/CeO2 catalysts under periodic CO <-> H2O feeds at 350 degrees C. The results provide quantitative evidence of the redox-based mechanism of the reaction and suggest that Ce3+- reoxidation by H2O has a lower barrier than Ce4+-O reduction. The number of interfacial sites between CeO2 and Cu species affects the turnover frequencies for the redox reaction and CO2/H-2 formation. An associative redox mechanism based on the redox reaction between Cu2+-OH and Ce4+-OH/Ce4+ and Cu+--Ce3+ is proposed as the main catalytic cycle of the reaction.
Article
Multidisciplinary Sciences
Shunsaku Yasumura, Kenichiro Saita, Takumi Miyakage, Ken Nagai, Kenichi Kon, Takashi Toyao, Zen Maeno, Tetsuya Taketsugu, Ken-ichi Shimizu
Summary: Automated reaction route mapping is used to design catalysts for low-temperature CH4 combustion with ozone. A suitable proton-type zeolite catalyst with Bronsted acid sites was predicted and shown to have superior performance in CH4 combustion.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Nat Phongprueksathat, Kah Wei Ting, Shinya Mine, Yuan Jing, Ryo Toyoshima, Hiroshi Kondoh, Ken-ichi Shimizu, Takashi Toyao, Atsushi Urakawa
Summary: Low temperature and high pressure are advantageous conditions for achieving high conversion and selectivity in CO2 hydrogenation. Re/TiO2 has been identified as a promising catalyst with higher activity than the industrial Cu/ZnO/Al2O3 catalyst at high pressure and low temperature. The study provides insights into the nature of active sites and active species, demonstrating the active role of cationic Re species in CO2 activation and formate intermediate formation.
Article
Chemistry, Physical
Yuan Jing, Chenxi He, Ningqiang Zhang, Yu Murano, Ryo Toyoshima, Hiroshi Kondoh, Yuuta Kageyama, Hironori Inomata, Takashi Toyao, Ken-ichi Shimizu
Summary: In this study, the addition of Ag was found to enhance the catalytic efficiency of RhOx/Al2O3 catalyst, especially at low temperatures. The promotional effect was mainly achieved by enhancing the thermal reduction of Rh oxide.
Article
Chemistry, Multidisciplinary
Shunsaku Yasumura, Takashi Kamachi, Takashi Toyao, Ken-ichi Shimizu, Yoyo Hinuma
Summary: This study proposes the unsaturated coordination index, σ, as a potential descriptor for the stability of metal-oxide surfaces. The value of σ, representing the number of missing bonds per unit area, can be quickly obtained using only crystallographic data, specifically the bulk geometry. The calculated surface energies of various binary oxides show good correlations with σ, particularly in high-symmetry crystals. This descriptor is useful for an initial evaluation of stable metal-oxide surfaces without the need for surface model calculations.
Article
Chemistry, Physical
Shunsaku Yasumura, Ken Nagai, Yucheng Qian, Takashi Toyao, Zen Maeno, Ken-ichi Shimizu
Summary: Rh-loaded mordenite zeolite was used as a catalyst for NO reduction using CO + H2O as a H2 source. Operando IR measurements revealed that Rh dicarbonyl species ([Rh(CO)(2)](+)) captured CO in the zeolite, which reacted with H2O to produce H(2)via the water gas shift (WGS) reaction. TPSR measurements showed that the formed H-2 was directly used for NO reduction into NH3. The study also investigated the mechanism of the WGS reaction.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Huang Mengwen, Shinsaku Yasumura, Takashi Toyao, Ken-ichi Shimizu, Zen Maeno
Summary: Metal-exchanged zeolites show potential for catalyzing small molecules like light alkanes by forming unique active metal species. Ga-exchanged zeolites have been studied extensively as heterogeneous catalysts for dehydrogenation of light alkanes. However, research on In-exchanged zeolites and their active species has been limited. This study summarizes investigations on In- and Ga-exchanged zeolites for light-alkane transformations, including the formation of In-oxo clusters and In-hydrides, as well as the catalytic properties of Ga-oxo clusters and Ga-hydrides.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Shunsaku Yasumura, Taisetsu Kato, Takashi Toyao, Zen Maeno, Ken-ichi Shimizu
Summary: By using the SC-AFIR algorithm, the catalytic reaction of NO and OH/OOH species over the Ag-4(2+) cluster in a zeolite was investigated. It was found that the formation of OH and OOH species has lower activation barriers, and the addition of hydrogen promotes their formation, thus enhancing the activity of the SCR reaction. The study highlights the power of automated reaction route mapping in elucidating complicated reaction pathways on multi-nuclear clusters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Engineering, Environmental
Lingcong Li, Ningqiang Zhang, Ziyang Wu, Shinta Miyazaki, Takashi Toyao, Zen Maeno, Ken-ichi Shimizu
Summary: Ni-based dual-functional materials (DFMs) have been extensively studied for CO2 capture and reduction with H2 (CCR); however, controlling the selectivity of CO2 hydrogenation to CH4 or CO is a challenge; in this study, Rb-Ni/Al2O3 is developed as an effective DFM for selective CO production through CCR at isothermal conditions, achieving high CO2 conversion and CO selectivity.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Ningqiang Zhang, Yucheng Qian, Takashi Toyao, Ken-ichi Shimizu
Summary: This article reports a new de-NOx system that uses cyclic feeds of rich and lean gas mixtures with PGM-free catalysts, showing higher NOx conversion compared to steady-state reactions. The mechanism under periodical rich/lean conditions was studied and a new urea-free and PGM-free catalytic system was demonstrated.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Mengwen Huang, Yosuke Tomimuro, Shinta Miyazaki, Shinya Mine, Takashi Toyao, Yoyo Hinuma, Yasuharu Kanda, Masaaki Kitano, Ken-ichi Shimizu, Zen Maeno
Summary: This study investigates propane metathesis reactions over metal hydrides, with TiH2 showing the highest butane yield. Fully-hydrogenated TiH2 is more active than dehydrogenated TiH and Ti metal. Surface low-valent Ti species on TiH2 are involved in the propane metathesis reaction. This study is the first to observe carbon-carbon bond cleavage and catalytic formation over bulk metal hydrides.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Mengwen Huang, Tetsuya Kinjo, Shunsaku Yasumura, Takashi Toyao, Daiju Matsumura, Hiroyuki Saitoh, Ken-ichi Shimizu, Norikazu Namiki, Zen Maeno
Summary: This study investigates the catalytic performance of Ga-exchanged zeolites at actual operating temperatures using in situ analysis. The results show that Ga-exchanged zeolites exhibit higher absorption peak intensity under hydrogen and ethane atmospheres, indicating the importance of hydride species in their catalytic activity.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Organic
Geeta Devi Yadav, Pooja Chaudhary, Balaram Pani, Surendra Singh
Summary: Chiral transition metal complexes with privileged ligands are efficient catalysts for various asymmetric organic transformations. Transition metal complexes of C1-symmetric pyrrolidine-based ligands have been widely used in asymmetric organic reactions. However, a comprehensive review article on the transition metal complexes of chiral C1-symmetric pyrrolidine-based ligands derived from (L)-proline has not been published.
TETRAHEDRON LETTERS
(2024)
