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iron-catalyzed reductive cyclization of nitroarenes: Synthesis of aza-heterocycles and DFT calculations

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Chinese Chemical Letters 2023年第3期34卷 337-341页

作者： Christine Tran Aicha Abdallah Valentin Duchemann Guillaume Lefevre Abdallah Hamze CNRS BioCISUniversitéParis-SaclayChatenay-Malabry 92290France Chimie ParisTech CNRSInstitute of Chemistry for Life and Health SciencesPSL UniversityCSB2DParis 75005France

Research into environmentally friendly strategies for hydrogen transfer reduction is increasing, along with the need for more elaborate heterocyclic platforms. Within this context, we develop a new approach for substituted dihydrobenzo[c]carbazoles and indoles. These compounds were synthesized through an iron-catalyzed hydrogen transfer reduction of nitroarenes, followed by intramolecular cyclization. This transformation involves using a Kn?lker-type catalyst, Cs_(2)CO_(3) as the base, and benzyl alcohol as the nonexpensive and low volatile hydrogen donor. We synthesize 30 examples of aza-heterocycles with moderate to excellent yields by applying this strategy. Additionally, DFT calculations demonstrated that the pathway reaction could follow an anionic mechanism.

关键词： iron Cyclization Nitroarenes Dihydrobenzo[c]carbazoles Indoles

iron,the endolysosomal system and neuroinflammation:a matter of balance

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Neural Regeneration Research 2022年第5期17卷 1003-1004页

作者： Daniel A.Bórquez Pamela J.Urrutia Marco T.Núñez Center for Biomedical Research Faculty of MedicineUniversidad Diego PortalesSantiagoChile Department of Biology Faculty of SciencesUniversidad de ChileSantiagoChile

iron accumulation and neuroinflammation are cardinal features of many neurodegenerative diseases(Urrutia et al.,2021).However,the hierarchy in the pathogenic mechanisms and the molecular connections between these proc... 详细信息

关键词： iron system showing

Vicious cycle of lipid peroxidation and iron accumulation in neurodegeneration

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Neural Regeneration Research 2023年第6期18卷 1196-1202页

作者： Instituto de Salud Carlos III Irene Villalón-García Suleva Povea-Cabello MónicaÁlvarez-Córdoba Marta Talaverón-Rey Juan MSuárez-Rivero Alejandra Suárez-Carrillo Manuel Munuera-Cabeza Diana Reche-López Paula Cilleros-Holgado Rocío Piñero-Pérez JoséA.Sánchez-Alcázar Centro Andaluz de Biología del Desarrollo(CABD-CSIC-Universidad Pablo de Olavide de Sevilla) and Centro de Investigación Biomédica en Red:Enfermedades RarasInstituto de Salud Carlos IIISevillaSpain

Lipid peroxidation and iron accumulation are closely associated with neurodegenerative diseases,such as Alzheimer’s,Parkinson’s,and Huntington’s diseases,or neurodegeneration with brain iron accumulation disorders.Mitochondrial dysfunction,lipofuscin accumulation,autophagy disruption,and ferroptosis have been implicated as the critical pathomechanisms of lipid peroxidation and iron accumulation in these disorders.Currently,the connection between lipid peroxidation and iron accumulation and the initial cause or consequence in neurodegeneration processes is unclear.In this review,we have compiled the known mechanisms by which lipid peroxidation triggers iron accumulation and lipofuscin formation,and the effect of iron overload on lipid peroxidation and cellular function.The vicious cycle established between both pathological alterations may lead to the development of neurodegeneration.Therefore,the investigation of these mechanisms is essential for exploring therapeutic strategies to restrict neurodegeneration.In addition,we discuss the interplay between lipid peroxidation and iron accumulation in neurodegeneration,particularly in PLA2G6-associated neurodegeneration,a rare neurodegenerative disease with autosomal recessive inheritance,which belongs to the group of neurodegeneration with brain iron accumulation disorders.

关键词： 4-hidroxynonenal ferroptosis iron lipid peroxidation lipofuscin neurodegeneration neurodegeneration with brain iron accumulation oxidative stress PLA2G6-associated neurodegeneration

The ferroxidases LPR1 and LPR2 control iron translocation in the xylem of Arabidopsis plants

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Molecular Plant 2022年第12期15卷 1962-1975页

作者： Zhong-Rui Xu Mei-Ling Cai Ying Yang Ting-Ting You Jian Feng Ma Peng Wang Fang-Jie Zhao State Key Laboratory of Crop Genetics and Germplasm Enhancement College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Institute of Plant Science and Resources Okayama UniversityChuo 2-20-1Kurashiki 710-0046Japan Academy for Advanced Interdisciplinary Studies Nanjing Agricultural UniversityNanjing 210095China

iron(Fe)deficiency is common in agricultural crops and affects millions of people worldwide.Translocation of Fe in the xylem is a key step for Fe distribution in plants.The mechanism controlling this process remains largely unknown.Here,we report that two Arabidopsis ferroxidases,LPR1 and LPR2,play a crucial and redundant role in controlling Fe translocation in the xylem.LPR1 and LPR2 are mainly localized in the cell walls of xylem vessels and the surrounding cells in roots,leaves,and stems.Knockout of both LPR1 and LPR2 increased the proportion of Fe(II)in the xylem sap,and caused Fe deposition along the vascular bundles especially in the petioles and main veins of leaves,which was alleviated by blocking blue light.The lpr1 lpr2 double mutant displayed constitutive expression of Fe deficiency response genes and overaccumulation of Fe in the roots and mature leaves under Fe-sufficient supply,but Fe deficiency chlorosis in the new leaves and inflorescences under low Fe supply.Moreover,the lpr1 lpr2 double mutant showed lower Fe concentrations in the xylem and phloem saps,and impaired 57Fe translocation along the xylem.In vitro assays showed that Fe(III)-citrate,the main form of Fe in xylem sap,is easily photoreduced to Fe(II)-citrate,which is unstable and prone to adsorption by cell walls.Taken together,these results indicate that LPR1 and LPR2 are required to oxidize Fe(II)and maintain Fe(III)-citrate stability and mobility during xylem translocation against photoreduction.Our study not only uncovers an essential physiological role of LPR1 and LPR2 but also reveals a new mechanism by which plants maintain Fe mobility during long-distance translocation in the xylem.

关键词： iron xylem translocation ferroxidases LPR1 LPR2 iron redox

Selective separation of iron and scandium from Bayer Sc-bearing red mud

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Journal of Rare Earths 2023年第7期41卷 1099-1107,I0005页

作者： Junhui Xiao Kai Zou Nanlan Zhong Deqiang Gao Sichuan Provincial Engineering Lab of Nonmetallic Mineral Powder Modification and High-Value Utilization Southwest University of Science and TechnologyMianyang 621010China Dongfang Boiler Group Co. Ltd.Zigong 643001China Key Laboratory of Ministry of Education for Solid Waste Treatment and Resource Recycle Southwest University of Science and TechnologyMianyang 621010China

In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·SiO_(2))as the main Fe-bearing minerals.The Sc-bearing red mud was treated by a novel deep reduction roasting and magnetic separation process that includes the addition of coke and CaO to extract Fe and enriching Sc from the Sc-bearing red mud.The addition of coke and CaO enhances the transformation of hematite(Fe_(2)O_(3))to metallic iron(Fe~0)and magnetite(Fe_(3)O_(4))as well as the transformation of ferrosilite into metallic iron(Fe~0).The test results show that utilizing the new process a Fe concentrate with a TFe content of 81.22 wt%and Fe recovery of 92.96%was obtained.Furthermore,magnetic separation tailings with Sc content of 0.0062 wt%and Sc recovery of 98.65%were also obtained.The test results were achieved under the following process conditions:roasting temperature of 1373 K,roasting time of 45 min,calcium oxide dosage of 20 wt%,coke dosage of 25 wt%,grinding fineness of90%iron(Fe~0)and magnetite(Fe_(3)O_(4)).The main minerals in the magnetic separation tailings with a low TFe content of 2.62%are CaO·SiO_(2),Na_(2)O·SiO_(2),FeO·SiO_(2),Ca_(3)Fe_(2)Si_(3)O_(12),CaAl_(2)SiO_6 and CaFe(SiO_(3))_(2).

关键词： Red mud Scandium iron Deep reduction roasting Magnetic separation Rare earths

The anisotropy of hexagonal close-packed iron under inner core conditions: the effect of light elements

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Earth and Planetary Physics 2022年第4期6卷 399-423页

作者： Wei Zhang Mei Tang ZhenWei Niu Laboratory for Extreme Conditions Matter Properties Southwest University of Science and TechnologyMianyang Sichuan 621010China Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Science and TechnologyMianyang Sichuan 621010China School of National Defense Science&Technology Southwest University of Science and TechnologyMianyang Sichuan 621010China

In recent decades,global seismic observations have identified increasingly complex anisotropy of the Earth’s inner core.Numerous seismic studies have confirmed hemispherical variations in the inner core’s anisotropy.Here,based on ab initio molecular dynamics calculations,we report how the anisotropy of hexagonal close-packed(hcp)-iron,under inner core conditions,could be altered when alloyed with light elements.We find that light elements in binary allows with iron-hcp-Fe-X(X=C,O,Si,and S)-could have significant effects on density,sound velocities,and anisotropy,compared with the behavior of pure hcp-iron;the anisotropy of these binary alloys depends on combined effects of temperature and the particular alloying light element.Furthermore,the change in anisotropy strength with increasing temperature can be charted for each alloy.Alloying pure iron with some light elements such as C or O actually does not increase but decreases core anisotropy at high temperatures.But the light element S can significantly enhance the elastic anisotropy strength of hcp-Fe.

关键词： iron elastic constants anisotropy inner core

Leaching process of phosphorus and iron from steelmaking slag into malic acid solution

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Journal of iron and Steel Research(International) 2022年第6期29卷 951-960页

作者： Ning-ning Lv Chang Su Hui Kong Hai-chuan Wang Yuan-chi Dong Key Laboratory of Metallurgical Emission Reduction and Resources Recycling Ministry of EducationAnhui University of TechnologyMa’anshan 243002AnhuiChina School of Metallurgical Engineering Anhui University of TechnologyMa’anshan 243002AnhuiChina

In order to remove phosphorus element from steelmaking slag and decrease iron loss,malic acid was selected as the leaching agent to dissolve steelmaking slag.Firstly,the influences of different factors,such as malic acid concentration,slag particle size,temperature,liquid/solid ratio and stirring speed,on the leaching ratios of phosphorus and iron were studied.Then,the kinetics for the leaching process of phosphorus was analyzed.The results showed that the leaching ratios of phosphorus and iron increase significantly with increasing the malic acid solution concentration and liquid/solid ratio.When the concentration of malic acid solution increases up to 0.01492 mol/L,about 80%phosphorus can be dissolved,and iron leaching ratio is less than 17%.In addition,decreasing slag particle size can obviously increase the leaching ratio of phosphorus.However,temperature and stirring speed have no significant effect on the dissolution of phosphorus and iron.The leaching kinetics of phosphorus follows the unreacted shrinking core model.Diffusion through product layer is the rate-limiting step of the leaching process,and the corresponding apparent activation energy is determined to be 3.32 kJ/mol.Finally,a semi-empirical kinetic equation was established.

关键词： Leaching process Steelmaking slag Phosphorus iron Malic acid solution

One-step separation and recovery of rare earth and iron from NdFeB slurry via phosphoric acid leaching

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Journal of Rare Earths 2022年第2期40卷 338-344,I0006页

作者： Ling He Qipeng Xu Wensheng Li Qizheng Dong Weimin Sun State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

The recovery of rare earth elements(REEs)from NdFeB slurry by traditional hydrometallurgy has been limited becuase a large number of REEs are lost during separation together with iron.In this paper,a simple and sustainable method is proposed to efficiently separate and recover REEs and iron from NdFeB slurry.REEs were recovered by one-step selective precipitation in phosphoric acid,and the dissolved iron was recovered by oxalic acid.Phosphoric acid leaching results show that under the conditions of 4 mol/L phosphoric acid,80℃,L/S of 30:1 and 90 min,the leaching efficiencies of Fe and REEs reach 98.76%and1.09%,respectively.While the rest of REEs remained in the leaching residue in the form of REEPO_(4)·nH_(2)O precipitation.Subsequently.the mixed rare earth oxide(rare earth oxalate roasted at 800℃)and FeC_(2)O_(4)·2 H_(2)O are obtained by oxalic acid precipitation with purities of 99.49%and 97.17%from the REEPO4·nH_(2)O dissolving solution and the phosphoric acid leaching solution.Moreover,the phosphoric acid is regenerated while recovering iron,and it can be reused in the phosphoric acid leaching step after removing the impurity C_(2)O_(4)^(2-).In summary,this work provides an efficient and environmentally friendly method for recovering REEs and iron from NdFeB slurry waste.

关键词： NdFeB slurry Phosphoric acid leaching iron Rare earth elements Oxalic acid

Accelerated biodegradation of iron-based implants via tantalum-implanted surface nanostructures

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Bioactive Materials 2022年第3期7卷 239-250页

作者： Min-Kyu Lee Hyun Lee Cheonil Park In-Gu Kang Jinyoung Kim Hyoun-Ee Kim Hyun-Do Jung Tae-Sik Jang Department of Materials Science and Engineering Seoul National UniversitySeoul08826Republic of Korea Querrey Simpson Institute for Bioelectronics Northwestern UniversityEvanstonIL60208USA Department of Biomedical-Chemical Engineering Catholic University of KoreaBucheon14662Republic of Korea Department of Biotechnology The Catholic University of KoreaBucheon14662Republic of Korea Department of Materials Science and Engineering Chosun UniversityGwangju61452Republic of Korea

In recent years,pure iron(Fe)has attracted significant attention as a promising biodegradable orthopedic implant material due to its excellent mechanical and biological properties.However,in physiological conditions,Fe has an extremely slow degradation rate with localized and irregular degradation,which is problematic for practical applications.In this study,we developed a novel combination of a nanostructured surface topography and galvanic reaction to achieve uniform and accelerated degradation of an Fe implant.The target-ion induced plasma sputtering(TIPS)technique was applied on the Fe implant to introduce biologically compatible and electrochemically noble tantalum(Ta)onto its surface and develop surface nano-galvanic couples.Electrochemical tests revealed that the uniformly distributed nano-galvanic corrosion cells of the TIPS-treated sample(nano Ta-Fe)led to relatively uniform and accelerated surface degradation compared to that of bare Fe.Furthermore,the mechanical properties of nano Ta-Fe remained almost constant during a long-term in vitro immersion test(~40 weeks).Biocompatibility was also assessed on surfaces of bare Fe and nano Ta-Fe using in vitro osteoblast responses through direct and indirect contact assays and an in vivo rabbit femur medullary cavity implantation model.The results revealed that nano Ta-Fe not only enhanced cell adhesion and spreading on its surface,but also exhibited no signs of cellular or tissue toxicity.These results demonstrate the immense potential of Ta-implanted surface nanostructures as an effective solution for the practical application of Fe-based orthopedic implants,ensuring long-term biosafety and clinical efficacy.

关键词： iron Tantalum Ion implantation Biodegradation Orthopedic implants