Article
Chemistry, Organic
Ju Hyeon An, Kyu Dong Kim, Jun Hee Lee
Summary: This new room-temperature deoxygenation method utilizing visible light-mediated metallaphotoredox catalysis, with Hantzsch esters as the reductant, efficiently deoxygenates various functionalized N-heterocyclic N-oxides, providing high yields and fast reaction rates.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Ashok A. Pise, Ajit P. Ingale, Navnath R. Dalvi
Summary: The developed reaction of amine N-tert-butyloxycarbonylation using sulfated polyborate under ultrasonic irradiation is demonstrated to have a broad substrate scope and excellent yields. The protocol offers advantages such as easy catalyst and product isolation, short reaction time, high selectivity, and recyclability, making it a practical, economical, and environmentally friendly process.
SYNTHETIC COMMUNICATIONS
(2021)
Article
Polymer Science
Devid Hero, Gergely Kali
Summary: The synthesis of linear polyisobutylene by free radical polymerization in aqueous medium using cyclodextrin solubilizer is reported. This method also led to the formation of new poly(isobutylene-co-acrylamide) amphiphilic copolymers. Additionally, reversible addition-fragmentation chain transfer radical polymerization of isobutylene using a PEG-based symmetric macro chain transfer agent resulted in the formation of Poly(PEG-b-isobutylene-b-PEG) block-copolymer. This novel polymerization method offers environmentally benign routes for producing novel copolymers.
EUROPEAN POLYMER JOURNAL
(2021)
Article
Chemistry, Inorganic & Nuclear
Nutchanikan Phiromphu, Methasit Juthathan, Pattira Suktanarak, Mongkol Sukwattanasinitt, Thawatchai Tuntulani, Pannee Leeladee
Summary: Simple and green conditions for copper-catalysed ATRA reactions in water have been developed. By adding a biocompatible surfactant, the reaction can be efficiently catalysed under mild conditions.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Ana Barra, Oana Lazar, Aida Pantazi, Maria J. Hortiguela, Gonzalo Otero-Irurueta, Marius Enachescu, Eduardo Ruiz-Hitzky, Claudia Nunes, Paula Ferreira
Summary: A green, simple, and cost-effective one-step reduction methodology using caffeic acid as reducing agent is presented in this study. The improvement of hydrothermal reduction in the presence of CA is confirmed by experimental analyses, showing promising applications for the synthesized rGO.
Article
Chemistry, Physical
Hao Xu, Peng He, Zhaofei Li, Shijun Meng, Yimeng Li, Lo-Yueh Chang, Lijia Liu, Xiaodong Wen, Brittney A. Klein, Vladimir K. Michaelis, Jizhen Qi, Dongchang Wu, Xi Liu, Hua Song
Summary: This study demonstrates a novel desulfurization process using methane as a regulator and generating CS2 as a sulfur-containing product. The catalytic mechanism is proposed and supported by experimental evidence.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Materials Science, Paper & Wood
Kydyrmolla Akatan, Sana Kabdrakhmanova, Tilek Kuanyshbekov, Zhanar Ibraeva, Ainur Battalova, K. S. Joshy, Sabu Thomas
Summary: The main focus of this study was to extract microcrystalline cellulose (MCC) from sunflower seed husks using the organosolvent oxidation method, and to carefully refine cellulose nanocrystals (CNCs). Physico-chemical characterization of the extracted materials showed promising structural and thermal properties. This research provides a cost-effective and environmentally benign approach for extracting cellulose from agricultural biomass waste.
Article
Chemistry, Multidisciplinary
Man Wang, Gan Liang, Yunhao Wang, Tao Fan, Baoling Yuan, Mingxian Liu, Ying Yin, Liangchun Li
Summary: Two highly efficient metal-organic framework catalysts have been synthesized through solvothermal reactions, with highly active nitroxyl catalytic sites for efficient oxidation reactions of alcohols and benzyl compounds under mild conditions. The system is environmentally friendly and sustainable with a simple work-up procedure.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Channa Basappa Vagish, Achutha Dileep Kumar, Karthik Kumara, Hamse Kameshwar Vivek, Nagamallu Renuka, Neratur Krishnappagowda Lokanath, Kariyappa Ajay Kumar
Summary: Oxidative stress is a major factor in neurogenerative diseases, and the search for effective antioxidants to combat this stress is crucial. The synthesis of novel antioxidants in this study showed promising results in reducing oxidative stress in the body by enhancing superoxide dismutase activity. Further research on these antioxidant molecules may lead to new treatments for oxidative stress-related diseases.
JOURNAL OF THE IRANIAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Youngsuk Kim, Jung Eun Byeon, Gu Yoon Jeong, Seoung Su Kim, Hayoung Song, Eunsung Lee
Summary: This study presents the design and synthesis of a novel organic radical based on a 1,2-dicarbonyl scaffold supported by N-heterocyclic carbenes (NHCs), which exhibits remarkable stability due to the steric and electronic stabilization provided by the two NHC moieties. The radical cations can tolerate various harsh conditions and surpass the stability of triphenylmethyl and TEMPO radicals.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Engineering, Chemical
Xudong Zhang, Junyao Wang, Jun Shen, Yugao Wang, Gang Liu, Yanxia Niu, Qingtao Sheng
Summary: This study investigated the extraction of indole from wash oil using deep eutectic solvents (DESs). TPAC/EG showed the highest extraction ability among the five DESs tested. By optimizing the experimental parameters, the extraction efficiency and purity of indole were significantly improved. In addition, a water-based regeneration method for DES was explored, demonstrating the reusability of DES.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Caiyun Xu, Haihong Wu, Zhanrong Zhang, Bingxiao Zheng, Jianxin Zhai, Kaili Zhang, Wei Wu, Xuelei Mei, Mingyuan He, Buxing Han
Summary: Chemoselective hydrodeoxygenation (HDO) of aromatic alcohols with excellent selectivity and high yields was achieved using porous carbon-nitrogen hybrid material-supported Co catalysts. This method opens up a way for efficient HDO reactions of aromatic alcohols using non-noble metal catalysts.
Article
Green & Sustainable Science & Technology
Mukesh Tanwar, Mousumi Debnath, Sharmista Debnath, Priyanka Sharma, Anoop Mukhopadhay, Nipun Kakar, Seeram Ramakrishna
Summary: Extremophilic microbial proteases are valuable sources of detergent additives due to their stability and activity. Immobilization techniques can improve product yield and stability, making them ideal for use in laundry detergents.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Chemistry, Organic
Fedor Kliuev, Anton Kuznetsov, Oleg I. Afanasyev, Sofiya A. Runikhina, Ekaterina Kuchuk, Evgeniya Podyacheva, Alexey A. Tsygankov, Denis Chusov
Summary: NaH2PO2 has been found to be an effective reducing agent in promoting reductive amination. It possesses characteristics of being nontoxic, stable, environmentally friendly, and readily available in large quantities, making it a potential competitor to classical reductants used in the target process. A low E factor of 1 was achieved for the substrate scope. Various carbonyl compounds reacted with amines under the developed conditions, demonstrating compatibility with a wide range of functional groups. The reaction conditions were successfully scaled up to 200-fold.
Article
Environmental Sciences
Andrew J. Carrier, Megan Carve, Jeff Shimeta, Tony R. Walker, Xu Zhang, Ken D. Oakes, Kshitij C. Jha, Tim Charlton, Martina H. Stenzel
Summary: Marine biofouling has long been a problem with negative environmental impact, and the development of sustainable solutions is crucial. This article provides an overview of strategies for sustainable marine antifouling coatings, including their effectiveness, durability, and environmental impact. It discusses technical challenges, barriers, and incentives for market uptake, and emphasizes the importance of multi-stakeholder collaboration for the development of marketable and sustainable antifouling coating solutions.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Polymer Science
Beomsu Park, Masatoshi Tosaka, Shigeru Yamago
Summary: Isotactic poly(N, N-diethyl acrylamide) (i-PDEAA) was synthesized by ytterbium triflate/H2O-catalyzed radical polymerization and its single crystals were successfully grown from solution. The lattice constants of Form-1 crystal were determined, while those of Form-2 crystal were only roughly estimated. The study provided insights into the crystallization of i-PDEAA and its crystal polymorphisms.
Article
Polymer Science
Beomsu Park, Yuji Imamura, Shigeru Yamago
Summary: The role of alcohol in the Yb(OTf)(3)- and Y(OTf)(3)-catalyzed stereoselective radical polymerization of acrylamides is clarified in this study. Alcohol coordination to the metal triflate generates a new complex, increasing both the polymerization rate and stereocontrol. The importance of hydroxyl groups for increasing reactivity is strongly suggested by secondary isotope effects observed in the polymerization process.
Article
Chemistry, Multidisciplinary
Yuki Miyazawa, Zhe Wang, Misaki Matsumoto, Sayaka Hatano, Ivana Antol, Eiichi Kayahara, Shigeru Yamago, Manabu Abe
Summary: Curved pi-conjugated molecules and open-shell structures have been studied extensively for their impact on the spin-spin interactions and unique characteristics of compounds. The research results demonstrate that the ground-state spin multiplicity and in-plane aromaticity of molecules are influenced by the curvature and system size, leading to new insights in fundamental chemistry.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Polymer Science
Xiaopei Li, Tasuku Ogihara, Tatsuhisa Kato, Yasuyuki Nakamura, Shigeru Yamago
Summary: The termination mechanism of acrylonitrile's radical polymerization was determined through product analysis. The study revealed the presence of polarity- and viscosity-controlled pathways in the termination reaction.
Review
Polymer Science
Shigeru Yamago
Summary: Recent developments in one-step radical polymerization have allowed for precise control over the structure of hyperbranched polymers, with a new monomer design method successfully changing the reactivity of dormant groups and enabling control over branching structures.
Article
Chemistry, Organic
Ryo Murata, Zhe Wang, Yuki Miyazawa, Ivana Antol, Shigeru Yamago, Manabu Abe
Summary: This study demonstrates the SOMO-HOMO conversion in triplet carbenes embedded in cycloparaphenylene units for the first time. The unique electronic configuration is attributed to the high-lying HOMO from the curved pi-conjugated system and the low-lying SOMO-1 from the small carbene angle. Additionally, planar triplet carbenes like fluorenylidene were also found to exhibit SOMO-HOMO energy-converted electronic configurations.
Article
Polymer Science
Yuhan Jiang, Weijia Fan, Masatoshi Tosaka, Michael F. Cunningham, Shigeru Yamago
Summary: High molecular weight poly(butyl acrylate)s and diblock copolymers were successfully synthesized using water-soluble organotellurium chain transfer agents in water, achieving high monomer conversion rates and low viscosity due to stable latex formation. The presence of termination reactions in reversible deactivation radical polymerization has been a limiting factor for synthesizing HMW polymers, but high end group fidelity was confirmed through block copolymer synthesis under the current conditions.
Article
Polymer Science
Podchara Rattanakawin, Kenji Yoshimoto, Yuta Hikima, Shinsuke Nagamine, Yuhan Jiang, Masatoshi Tosaka, Shigeru Yamago, Masahiro Ohshima
Summary: A method of fabricating highly ordered nanocellular foam using UV-induced chemical foaming technique and self-assembly of block copolymer PMMA-b-PtBA was reported. Different self-assembled morphologies were investigated for their effects on the formation of nanocellular foams. It was found that cells generated from the lamella templates had higher expandability compared to those from the cylindrical templates. Increasing the molecular weight of PMMA could mitigate the drastic change in cell structure.
Article
Polymer Science
Hiroyuki Kojima, Yuji Imamura, Yangtian Lu, Shigeru Yamago, Tsuyoshi Koga
Summary: This study systematically synthesized structurally controlled hyperbranched poly(N-isopropylacrylamide)s with different branching densities and studied their phase behavior in water. The results show that the increase in branching density leads to a decrease in LCSTs. Theoretical analysis suggests that hydration behavior of branching points strongly influences the phase behavior, and hydration of end groups and branching points determines the binodal temperature.
Article
Chemistry, Multidisciplinary
Tomoaki Terabayashi, Eiichi Kayahara, Yichen Zhang, Yoshiyuki Mizuhata, Norihiro Tokitoh, Tohru Nishinaga, Tatsuhisa Kato, Shigeru Yamago
Summary: In this study, Mono-alkene-inserted [n]cycloparaphenylenes (CPPs) and Mono-ortho-phenylene-inserted [6]CPP were synthesized through coupling reactions, and it was found that they exhibited Mobius topology in the solid state. Although this structure is often lost in solution, ene-[6]CPP with 1-pyrrolyl groups preserved the Mobius topology even in solution.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Dongyang Chen, Yoshimasa Wada, Yu Kusakabe, Liansheng Sun, Eiichi Kayahara, Katsuaki Suzuki, Hiroyuki Tanaka, Shigeru Yamago, Hironori Kaji, Eli Zysman-Colman
Summary: In this study, we investigated the possibility of utilizing cycloparaphenylenes (CPP) in a donor-acceptor TADF emitter design. The compound 4PXZPh-[10]CPP, which contains four electron-donating groups connected to a [10]CPP, exhibited sky-blue emission with a wavelength of 475 nm and a photoluminescence efficiency of 29% in a 15 wt% doped CzSi film. Solution-processed OLEDs incorporating 4PXZPh-[10]CPP displayed sky-blue emission with a wavelength of 465 nm and a maximum external quantum efficiency of 1.0%.
Article
Polymer Science
Yuhan Jiang, Weijia Fan, Masatoshi Tosaka, Shigeru Yamago
Summary: In this study, structurally controlled high-molecular-weight (HMW) PSts and block copolymers were successfully synthesized using emulsion organotellurium-mediated radical polymerization (TERP). The method demonstrated high monomer conversion, high end-group fidelity, and rapid monomer diffusion, providing a valuable route for fabricating polymer materials based on HMW PSts.
Article
Chemistry, Multidisciplinary
Masatoshi Tosaka, Hinako Takeuchi, Masato Kibune, Tianxiang Tong, Nanyi Zhu, Shigeru Yamago
Summary: Stochastic simulation of the formation process of hyperbranched polymers (HBPs) using a branch-inducing monomer, evolmer, revealed that the observed dispersities (Ds) were due to the distribution of the number of branches instead of undesired side reactions. The simulation also showed that the branch structures were well controlled and the majority of HBPs had structures close to the ideal one. Furthermore, the simulation suggested a slight dependence of branch density on molecular weight, which was experimentally confirmed.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yuhan Jiang, Masato Kibune, Masatoshi Tosaka, Shigeru Yamago
Summary: The practical synthesis of structurally controlled hyperbranched polymers (HBPs) by organotellurium-mediated radical polymerization (TERP) in water under emulsion conditions is reported. The method allows for the controlled synthesis of HBPs with diverse branch structures and tunable polymer properties by changing the monomers used.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Polymer Science
Yuji Imamura, Shigeru Yamago
Summary: The reversible addition-fragmentation chain transfer (RAFT) polymerization of acrylamide in methanol using dithioester RAFT chain-transfer agent 2a was unsuccessful due to end group degradation, but this was suppressed by the addition of rare-earth metal triflates. The presence of RMTs allowed for the synthesis of high-molecular-weight poly(acrylamides) with controlled molecular weight and tacticity.