Article
Chemistry, Physical
Sangeth Jenthra, Totan Mondal, Gregor Kemper, Marcus Lantzius-Beninga, Markus Hoelscher, Walter Leitner
Summary: A highly chemo- and regioselective decarboxylative Heck-type coupling of carboxylic acids and terminal olefins was achieved using a catalytic system composed of Pd(OAc)(2) in the presence of phosphine-sulfonamido ligands. The bulky ligand L1 favored the formation of 1,1-disubstituted branched olefins with high selectivity, while the less bulky ligand L2 resulted in the formation of 1,2-disubstituted linear products in high yield. Detailed mechanistic investigation revealed that the aryl substituent at the sulfonamide group of ligand L1 favored 1,2-insertion, while the less bulky ligand L2 favored 2,1-insertion.
Article
Chemistry, Organic
Jenna N. Humke, Ryan A. Daley, Aaron S. Morrenzin, Sharon R. Neufeldt, Joseph J. Topczewski
Summary: This study investigates the mechanistic details of the palladium-catalyzed decarboxylative cross-coupling of sodium benzoates and chloroarenes. The reaction was found to be first-order in Pd, with minimal substituent effect observed for chloroarenes. Palladium-mediated decarboxylation was identified as the turnover-limiting step. The addition of exogenous XPhos was shown to significantly increase catalyst turnover number and improve reproducibility.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Chiara Palladino, Tommaso Fantoni, Lucia Ferrazzano, Beatrice Muzzi, Antonio Ricci, Alessandra Tolomelli, Walter Cabri
Summary: The copper-free Heck-Cassar-Sonogashira (HCS) reaction is a powerful method for C-C bond formation in organic synthesis and has several industrial applications. This study investigated the mechanism of the copper-free HCS reaction by conducting stoichiometric and catalytic reactions and analyzing the role of the base. The results showed that the base can accelerate the reduction of the precatalyst and decrease the energy barrier for the alkyne carbopalladation step.
Article
Chemistry, Organic
Huahua Liu, Yuping Xiong, Zhiyuan Chen
Summary: An efficient intramolecular Heck annulation reaction and trapping of the resulting cyclic alpha-oxindolylpalladium species by CO and NH-sulfoximine at room temperature has been demonstrated, providing excellent yields of 3,3-disubstituted beta-indoly sulfoximidoyl amides under very gentle reaction conditions.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Acoustics
Ali Mojed, Rouholah Ashiri, Ali Shafyei
Summary: Titanate-based perovskite powders are widely used for ceramic capacitors and a new ultrasound-assisted precipitation method is introduced for synthesizing high-quality perovskite nanocrystals at room temperature.
ULTRASONICS SONOCHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Fang Peng, Yian Chen, Hongchen Liu, Pan Chen, Feng Peng, Haisong Qi
Summary: This study presents the synthesis of cellulose derivatives with 1,4-dihydropyridine rings, resulting in materials with ultralong room-temperature phosphorescence. The cellulose films also exhibit excitation-dependent and water stimulus-response afterglows, making them suitable for applications in information encryption and anti-counterfeiting.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Lihua Zhu, Huaze Zhu, Mohsen Shakouri, Linghai Zeng, Zhiqing Yang, Yongfeng Hu, Hengqiang Ye, Hui Wang, Bing Hui Chen, Rafael Luque
Summary: This study proposed a novel strategy to design highly efficient and stable multimetallic catalysts for heterogeneous catalytic hydrogenation reactions, utilizing the interfacial nano-synergy effect among different metallic related species. The reduced Rh/NiCo/CNTs catalyst exhibited significantly improved catalytic activity at room temperature compared to single metal catalysts.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Organic
Wei-Yi Ding, Huan-Huan Liu, Jun Kee Cheng, Hui Yao, Shao-Hua Xiang, Bin Tan
Summary: Despite the increasing importance of C-glycosides in biochemistry, the strategies for achieving stereoselective C-glycosidic bond formation have received less attention compared to those for O- and N-glycosides. In this study, a beta-C-glycosylation of oxazol-5(4H)-ones, which serve as direct precursors of amino acids, was described. Regardless of the glycal donors and glycosyl acceptors used, the reaction displayed excellent efficiency and chemoselectivity in most cases without the need for exogenous bases. The outstanding stereocontrol at the anomeric center was attributed to the steric hindrance imposed by a bulky phosphine ligand.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Engineering, Environmental
Chunyan Ma, Shumei Sun, Hao Lu, Zhengping Hao, Chenggong Yang, Bin Wang, Cheng Chen, Maoyong Song
Summary: The study successfully synthesized a super water-resistant Akhtenskite-type MnO2 catalyst, exhibiting enhanced activity and stability for formaldehyde oxidation at room temperature in humid air. Characterization of H2O adsorption and intermediate species was done using diffuse-reflectance infrared Fourier transform (DRIRFT) spectroscopy.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Samir Manna, Shunta Kakumachi, Kanak Kanti Das, Youichi Tsuchiya, Chihaya Adachi, Santanu Panda
Summary: The solvent plays a crucial role in the photophysical properties of donor-acceptor based photocatalysts. The access to E vs. Z-allylic amines, depending on the solvent, was achieved through decarboxylative vinylation of amino acids with vinyl sulfones. Detailed experimental studies were conducted to understand the role of the solvent in the reactivity and stereoselectivity of the vinylation reactions.
Article
Multidisciplinary Sciences
Hariom Jani, Jheng-Cyuan Lin, Jiahao Chen, Jack Harrison, Francesco Maccherozzi, Jonathon Schad, Saurav Prakash, Chang-Beom Eom, A. Ariando, T. Venkatesan, Paolo G. Radaelli
Summary: In the quest for post-CMOS technologies, researchers have shown promising results in experimenting with topologically protected ferromagnetic whirls such as skyrmions and their anti-particles, which can serve as solitonic information carriers. Antiferromagnetic analogues have become the subject of intense focus due to their predicted relativistic dynamics and potential for fast deflection-free motion and size scaling, although experimental demonstration in natural antiferromagnetic systems has yet to be achieved. By utilizing a first-order analogue of the Kibble-Zurek mechanism, a family of topological antiferromagnetic spin textures has been stabilized on an Earth-abundant oxide insulator, showing potential for low-energy antiferromagnetic spintronics at room temperature.
Article
Chemistry, Multidisciplinary
Junzhe Xiao, Yifan Cui, Can Li, Haibo Xu, Yizhan Zhai, Xue Zhang, Shengming Ma
Summary: The study developed a gold-catalyzed room temperature allenation of terminal alkynes with aldehydes, providing 1,3-disubstituted allenes with diverse functional groups, and demonstrated the practicality and synthetic potentials of this reaction. Mechanistic studies showed that the gold catalyst, the aldehyde effect, the fluoroalkyl hydroxyl solvent, and the structure of the amine are essential for this room temperature ATA reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Materials Science, Ceramics
Xudong Gao, Liuyang Gu, Wenjing Wei, Shuyi Sun, Liangliang Lv, Tong Li, Zhanzu Feng, Nannan Xu, Gongping Li
Summary: This study demonstrates that the generation of intrinsic defects in rutile TiO2 through electron irradiation can induce room temperature ferromagnetism. The type and concentration of defects can be controlled by adjusting the energy and fluence of the electron beam. The findings show that the changes in microstructure and magnetic-optical properties are similar to the variations in defect concentration.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Niels Lichtenberger, Maximilian Menche, Katharina S. L. Rueck, Rocco Paciello, Ansgar Schaefer, Peter Comba, A. Stephen K. Hashmi, Thomas Schaub
Summary: The (hydroxy)carbonylation of tertiary aliphatic alcohols and their corresponding olefins using a Ni-based catalyst system has been investigated. This study provides detailed mechanistic insights and expands the understanding of Ni-catalyzed carbonylation reactions.
Article
Nanoscience & Nanotechnology
O. J. Amin, S. F. Poole, S. Reimers, L. X. Barton, A. Dal Din, F. Maccherozzi, S. S. Dhesi, V. Novak, F. Krizek, J. S. Chauhan, R. P. Campion, A. W. Rushforth, T. Jungwirth, O. A. Tretiakov, K. W. Edmonds, P. Wadley
Summary: Researchers have discovered that topological spin textures can be generated and moved at room temperature using electrical pulses in the semimetallic antiferromagnet CuMnAs, which is a testbed system for spintronic applications. This finding is crucial for realizing the full potential of antiferromagnetic thin films as active components in high-density, high-speed magnetic memory devices.
NATURE NANOTECHNOLOGY
(2023)
