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Radical Arbuzov Reaction

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CCS chemistry 2024年第5期6卷 1312-1323页

作者： Linxiang Chai Jian Wang Jimin Yang Junyue Yin Zhuyong Zhang Yulu Cheng Lin Zhu Xiao-Song Xue Chaozhong Li department of chemistry University of Science and Technology of ChinaHefeiAnhui 230026 Shanghai institute of Organic chemistry Chinese Academy of SciencesShanghai 200032

The Arbuzov reaction(also known as the Michaelis–Arbuzov reaction)is one of the most fundamental transformations in organic chemistry and has been extensively used for the synthesis of organophosphorus compounds for over a ***,the reaction generally requires an elevated temperature and is applicable mainly to primary alkyl halides with poor functional group *** report herein a radical alternative to the conventional nucleophilic substitution ***,new radical phosphonylation reagents,9-fluorenyl o-phenylene phosphite and benzhydryl o-phenylene phosphite,have been developed for this *** photoredox-catalyzed reaction of a wide range of alkyl bromides or iodides with 9-fluorenyl(or benzhydryl)o-phenylene phosphite followed by workup with methanol(or ethanol)provides the corresponding dimethyl(or diethyl)alkylphosphonates in satisfactory yields at room temperature under mild *** method is applicable to primary,secondary,and even tertiary alkyl iodides and bromides and exhibits an excellent functional group tolerance,thereby enabling the late-stage modification of complex molecules and rapid synthesis of phosphonate-containing natural products and drug molecules.A mechanism involving the formation and subsequentβ-scission of phosphoranyl radicals is proposed.

关键词： Arbuzov reaction radicals phosphonylation photoredox catalysis alkyl halides

Strain-promoted S-arylation and alkenylation of sulfinamides using arynes and cyclic alkynes

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Science China chemistry 2024年第3期67卷 928-935页

作者： Xi Zou Boming Shen Gao-lin Li Qian Liang Yanhua Ouyang Binghe Yang Peiyuan Yu Bing Gao State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringInstitute of Chemical Biology and NanomedicineHunan UniversityChangsha 410082China department of chemistry and Shenzhen Grubbs institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China

The conversion of commercially available chiral sulfinamides into pharmaceutically useful chiral sulfoximines via direct SIVfunctionalization is synthetically attractive but challenging due to the competitive reaction of N-functionalization. Herein, we disclose a novel strain-release strategy to access stereospecific and chemoselective SIV-arylation and alkenylation of sulfinamides using arynes and strained cyclic alkynes. This method tolerates an unprecedented chemical diversity of functional groups attached to the nitrogen center(N-R). The origin of the high SIV-selectivity is elucidated by density functional theory calculations, suggesting a stepwise mechanism for the aryne substrates and a concerted mechanism for the cyclic alkynes.

关键词： arylation alkenylation sulfoximines sulfinamides arynes

Enhanced electromagnetic wave absorption via optical fiber-like PMMA@Ti_(3)C_(2)T_(x)@SiO_(2) composites with improved impedance matching

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Nano Research 2024年第3期17卷 1676-1686页

作者： Huanhuan Niu Xuewen Jiang Wei Li Zhiyu Min Budi Riza Putra Wulan Tri Wahyuni Hailong Wang Rui Zhang Bingbing Fan School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China School of Materials Science and Engineering Tongji UniversityShanghai 201804China department of Materials and Earth Sciences Technical University of DarmstadtDarmstadt 64287Germany School of Material Science and Engineering Luoyang Institute of Science and TechnologyLuoyang 471023China Research Center for Metallurgy National Research and Innovation Agency(BRIN)PUSPIPTEK Gd.470South TangerangBanten 15315Indonesia analytical chemistry Division Department of ChemistryFaculty of Mathematics and Natural SciencesIPB UniversityWest Java 16680Indonesia

Ti_(3)C_(2)T_(x) nanosheets have attracted significant attention for their potential in electromagnetic wave absorption(EWA).However,their inherent self-stacking and exorbitant electrical conductivity inevitably lead to serious impedance mismatch,restricting their EWA ***,the optimization of impedance matching becomes *** this work,we developed polymethyl methacrylate(PMMA)@Ti_(3)C_(2)T_(x)@SiO_(2) composites with a sandwich-like core–shell structure by coating SiO_(2) on PMMA@Ti_(3)C_(2)T_(x).The results demonstrate that the superiority of the SiO_(2) layer in combination with PMMA@Ti_(3)C_(2)T_(x),outperforming other relative graded distribution structures and meeting the requirements of EWA *** resulting PMMA@Ti_(3)C_(2)T_(x)@SiO_(2) composites achieved a minimum reflection loss of-58.08 dB with a thickness of 1.9 mm,and an effective absorption bandwidth of 2.88 *** analysis revealed that the structural design of SiO_(2) layer not only optimized impedance matching,but also synergistically enhanced multiple loss mechanisms such as interfacial polarization and dipolar ***,this work provides valuable insights for the future preparation of high-performance electromagnetic wave absorbing Ti_(3)C_(2)T_(x)-based composites.

关键词： polymethyl methacrylate(PMMA)@Ti_(3)C_(2)T_(x)@SiO_(2)composites impedance match SiO_(2)layer optical fiber-like structure interfacial polarization and dipolar polarization

Ni-catalyzed highly regio- and stereo-selective diborylative cyclization of 1,6-enynes with diboron reagent

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Science China chemistry 2024年第3期67卷 981-989页

作者： Qitao Guan Zhen Shen Yiqiang Tian Genping Huang Chun Zhang institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic ScienceDepartment of ChemistrySchool of SciencesTianjin UniversityTianjin 300072China State Key Laboratory of Elemento-Organic chemistry Nankai UniversityTianjin 300071China

The Ni-catalyzed highly selective diborylative cyclization of 1,6-enynes with diboron reagent has been developed. When pinB-Bdan was used, multiple types of boron-containing functional groups could be installed into organic molecule with great chemoselectivity and regioselectivity though this reaction. Meanwhile, if B_2pai_2 was employed, the asymmetric diborylative cyclization could be well induced by using strategy of dynamic kinetic resolution. Importantly, the above reactions could afford desired product with 100% atomic economy, and could be compatible with different series of substituents. The studies of further transformation well illustrated that different type products could serve diverse synthetic strategy. Notably, the reaction mechanism was intensively studied by density functional theory(DFT) calculations, which could reveal the mechanism of regio- and enantio-selective control.

关键词： nickel-catalyzed organoboron cyclization regioselectivity enantioselectivity

Ultralong hydroxyapatite-based forward osmosis membrane for freshwater generation

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 37-49页

作者： Mohamed Gamal Gomaa Hamdy Maamoun Abdel-Ghafar Francesco Galiano Francesca Russo Alberto Figoli El-Sayed Ali Abdel-Aal Abdel-Hakim Taha Kandil Bahaa Ahmed Salah Central Metallurgical Research and Development institute(CMRDI) 11421 CairoEgypt chemistry department Faculty of ScienceHelwan University11795 CairoEgypt institute on Membrane Technology(CNR-ITM) 87036 RendeItaly

Increasing global water shortages are accelerating the pace of membrane manufacturing,which generates many environmentally harmful *** challenges need a radical rethink of developing innovative membranes that can address freshwater production without generating environmentally harmful *** work utilized the synthesized ultra-long hydroxyapatite(UHA)by the solvothermal method using the green solvent oleic acid in preparing UHA-based forward osmosis *** membranes were developed using different loading ratios of graphene oxide(GO)by vacuum-assisted filtration *** prepared GO/UHA membranes were identified using X-ray diffraction,scanning electron microscope,Fourier-transform infrared spectroscopy,and X-ray photoelectron *** contact angle and pore size distribution were determined for the obtained GO/UHA *** obtained hierarchical porous structure in the prepared membranes with interconnected channels results in a stable water flux with reverse salt *** best water flux rate of 42±2 L·m^(–2)·h^(–1)was achieved using the 50 mg GO/UHA membrane,which is 3.3 times higher than the pristine membrane,and a reverse salt flux of 67 g·m^(-2)·h^(–1).The obtained results showed a promising capability of a new generation of sustainable inorganic-based membranes that can be utilized in freshwater generation by energy-efficient techniques such as forward osmosis.

关键词： forward osmosis ultra-long hydroxyapatite graphene oxide inorganic-based membrane

Surface morphologies of Mg-Gd alloy particle during its reactions with O_(2) and Teflon

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Defence Technology（防务技术） 2024年第3期33卷 209-221页

作者： Yifan Li Hongtao Yang Aifeng Jiang Dongming Song Yanchun Li department of Chemical Engineering Nanjing University of Science and TechnologyNanjing 210097China Xi'an Modern chemistry Research institute Xi'an 710065China Southwest Technology and Engineering Research institute Chongqing 400039China

Mg-Gd alloy particle has exhibited its unique combustion properties as the fuel of Mg/Teflon/Viton(MTV).Mg-Gd alloy/Teflon/Viton(MGTV)could burn at lower ambient pressure than *** further investigate the reaction of MGTV in air,it was investigated via thermo gravity-differential scanning calorimetry(TG-DSC).Meanwhile,the morphologies and element distributions on the alloy surface during the reaction of MGTV in air were investigated via scanning electronic microscope-mapping-electronic differential ***,a similar experimental protocol on the Mg-Gd alloy particle during oxidation was also *** results showed that owning to a protective oxide shell,the onset oxidation temperature of Mg-Gd alloy is higher than ***,the onset oxidation temperature of the exceeded Mg-Gd alloy in MGTV is significantly lower than that of the exceeded Mg in *** was due to the existence of GdOF,which could significantly lower the oxidation temperature of the exceeded ***,a possible reaction mechanism was *** fascinating oxidation properties of Mg-Gd alloy suggested its promising applications in energetic materials.

关键词： Mg-Gd alloy Energetic materials Morphology EDS GdOF

Research Progress in Enantioselective Radical Desymmetrization Reactions

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CCS chemistry 2024年第7期6卷 1612-1627页

作者： Chang-Jiang Yang Lin Liu Qiang-Shuai Gu Xin-Yuan Liu department of chemistry and Dongguan Key Laboratory for Data Science and Intelligent Medicine Great Bay UniversityDongguan 523000 Shenzhen Grubbs institute Department of Chemistryand Guangming Advanced Research InstituteSouthern University of Science and TechnologyShenzhen 518055 Academy for Advanced Interdisciplinary Studies and department of chemistry Southern University of Science and TechnologyShenzhen 518055

Enantioselective radical desymmetrization is a highly effective approach for rapidly creating enantioenriched molecules,introducing dramatically increased structural complexity from readily available prochiral or meso compound *** strategic modes have been developed for these reactions,which differ in the nature of the stereo-determining *** first category deals primarily with the stereoselective desymmetrization of closed-shell radical precursors or functional reagents,whereas the second category achieves desymmetrization by stereoselectively functionalizing open-shell radical *** mini-review explores the research progress in this growing field,aiming to elucidate mechanistic scenarios related to stereochemical ***,it offers insights into the challenges and opportunities that lie ahead for further development.

关键词： radical desymmetrization enantioselective desymmetrization radical functionalization transition metal catalysis asymmetric catalysis

Beneficial use of mussel shell as a bioadditive for TPU green composites by the valorization of an aqueous waste

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Waste Disposal and Sustainable Energy 2024年第1期6卷 123-137页

作者： SedefŞişmanoğlu Yasin Kanbur Carmen-Mihaela Popescu Diana Kindzera Ümit Tayfun department of chemistry Karabuk University78050KarabukTurkey Petru Poni institute of Macromolecular chemistry of the Romanian Academy 700487IasiRomania department of Chemical Engineering Lviv Polytechnic National UniversityLviv79013Ukraine department of Basic Sciences Bartin University74110BartinTurkey

Scientific studies have focused on environmentally friendly solutions as effective as the reuse of crop products owing to plastic-waste problems in recent *** issue is the main driving force for upcoming academic research attempts in waste valorization-related ***,we integrated an aqua-waste,mussel shell(MS),as a bioadditive form into green thermoplastic polyurethane(TPU)green *** of the MS surface was performed to achieve strong adhesion between composite *** surface functionalities of MS powders were evaluated via infrared spectroscopy and scanning electron microscopy(SEM)*** samples were prepared by melt-compounding followed by injection molding *** was confirmed by morphological analysis that relatively better adhesion between the phases was achieved for composites involving surface-modified MS compared to unmodified *** strength and Young’s modulus of surface-modified MS-filled composites were found to be higher than those of unmodified MS,whereas the elongation at break shifted to lower values with MS *** shore hardness of TPU was remarkably improved after being incorporated with silane-treated MS(AS-MS).Stearic acid-treated MS(ST-MS)additions resulted in an enhancement in the thermal stability of the ***-mechanical analysis showed that the storage moduli of composites were higher than those of unfilled ***-MS additions led to an increase in the characteristic glass transition temperature of *** flow index(MFI)of neat TPU was highly improved after MS loading regardless of modification *** to the wear test,surface modification of MS displayed a positive effect on the wear resistance of *** the water absorption data of the composites were evaluated,the TPU/AS-MS composite yielded the lowest water *** silane layer on MS inclusion promoted water repellency of composites due to the hydrophobicity of *** results of the biodegradation

关键词： Aqua-waste Polyurethane Mussel shell Green composites Sustainability Waste valorization

One dimensional pea-shaped NiSe_(2) nanoparticles encapsulated in N-doped graphitic carbon fibers to boost redox reversibility in sodium-ion batteries

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Journal of Materials Science & Technology 2024年第1期168卷 215-226页

作者： Hyunjeong Gim Achmad Yanuar Maulana Jiwon Choi Jungwook Song Boram Yun Yuri Jeong Nahyun An Myeongkee Park Cybelle M.Futalan Jongsik Kim department of Chemical Engineering(BK21 FOUR Graduate Program) Dong-A UniversityBusan 49315Korea(the Republic of) department of chemistry Dong-A UniversityBusan 49315Korea(the Republic of) department of chemistry Pukyong National UniversityBusan 48513Korea(the Republic of) institute of Civil Engineering University of the PhilippinesDiliman 1127Philippines

In recent years,sodium-ion batteries(SIBs)have emerged as a promising technology for energy storage systems(ESSs)because of the abundance and affordability of ***,metal selenides have been studied as promising high-performance conversion-type anode materials in *** them,nickel se-lenide(NiSe_(2))has received considerable attention due to its high theoretical capacity of 495 mAh g^(-1)and ***,it still suffers from poor cycling stability because of the low electrochemical reactivity,large volume expansion,and structural instability during *** address these challenges,NiSe_(2)nanoparticles encapsulated in N-doped graphitic carbon fibers(NiSe_(2)@NGCF)were synthesized by using ZIF-8 as a ***_(2)@NGCF showed a high discharge capacity of 558.3 mAh g^(-1)with a fading rate of 0.14%per cycle after 200 cycles at 0.5 A g^(-1)in 0.01-3.0 *** a very high current density of 5 A g^(-1),the capacity still displayed excellent long-term cycle life with a discharge capacity of 406.1 mAh g^(-1)with a fading rate of 0.016%per cycle after 3000 *** mechanism of the excellent electrochem-ical performance of NiSe_(2)@NGCF was thoroughly investigated by ex-situ XRD,TEM,and SEM ***,NiSe_(2)@NGCF//Na_(3)V_(2)(PO_(4))_(3)full-cell also delivered an excellent reversible capacity of 378.7 mAh g^(−1)at 0.1 A g^(−1)after 50 cycles,demonstrating its potential for practical application in SIBs.

关键词： Sodium-ion batteries Anode materials Nickel selenide N-doped graphitic carbon fibers One-dimensional electrode