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reductive recovery of manganese from low-grade manganese dioxide ore using toxic nitrocellulose acid wastewater as reductant

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International Journal of Minerals,Metallurgy and Materials 2018年第9期25卷 990-999页

作者： Yong-tao Zhang Zhi-gang Dan Ning Duan Bao-ping Xin School of Petroleum and Environment Engineering Yan'an University School of Materials Science & Engineering Beijing Institute of Technology Technology Center for Heavy Metal Cleaner Production Engineering Chinese Research Academy of Environmental Sciences

The hydrometallurgical strategy of extracting Mn from low-grade Mn ores has attracted attention for the production of electrolytic manganese metal(EMM). In this work, the reductive dissolution of low-grade Mn O2 ores using toxic nitrocellulose acidic wastewater(NAW) as a reductant was investigated for the first time. Under the optimized conditions of an Mn O2 ore dosage of 100 g·L-1, an ore particle size of-200 mesh, concentrated H2 SO4-to-NAW volume ratio of 0.12, reaction temperature of 90°C, stirring speed at 160 r·min-1, and a contact time of 120 min, the reductive leaching efficiency of Mn and the total organic carbon(TOC) removal efficiency of NAW reached 97.4% and 98.5%, respectively. The residual TOC of 31.6 mg·L-1 did not adversely affect the preparation of EMM. The current process offers a feasible route for the concurrent realization of the reductive leaching of Mn and the treatment of toxic wastewater via a simple one-step process.

关键词： low-grade manganese dioxide ore nitrocellulose acid wastewater sulfuric acid leaching Mn reductive dissolution electrolytic manganese metal

reductive Amination of Carbonyl Compounds with Ammonia and Hydrogenation of Nitriles to Primary Amines with Heterogeneous Cobalt Catalysts

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Chemical Research in Chinese Universities 2019年第3期35卷 457-462页

作者： LIU Junmei GUO Wanwan SUN Hao LI Ruyue FENG Zhipeng ZHOU Xuyang HUANG Jun State Key Laboratory ofMaterials-ori ented Chemical Engineering College of Chemical Engineering Nanjing Tech UniversityNanjing 210009P.R.China

reductive amination of aldehydes/ketones with aqueous NH3 and hydrogenation of nitriles to primary amines with Co catalysts were reported. Co@NC-700 exhibited remarkable activity and high selectivity for the reductive amination of aldehydes/ketones with aqueous NH3 and the hydrogenation of nitriles to primary amines. Several primary amines can be obtained with good to excellent yields via the reductive amination of aldehydes/ketones and the hydrogenation of nitriles. The nitrogen-doped carbon(C)-supported Co@NC-700 metal catalyst was prepared via the pyrolysis of bioMOF Co/adenine in activated C. Co@NC-700 can be reused five times without evident loss of activity.

关键词： Primary amine Cobalt reductive amination Aldehyde Hydrogenation Nitrile

Visible-light-mediated external-reductant-free reductive cross coupling of benzylammonium salts with(hetero)aryl nitriles

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Science China Chemistry 2019年第11期62卷 1519-1524页

作者： Meng Miao Li-Li Liao Guang-Mei Cao Wen-Jun Zhou Da-Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Chemistry and Chemical Engineering Neijiang Normal UniversityNeijiang 641100China

Herein we report a novel visible-light-mediated external reductant-free reductive cross coupling for the construction of C sp2–C sp3 bonds.A variety of benzylammonium salts underwent selective coupling with(hetero)aryl nitriles to deliver important diarylmethanes under mild reaction conditions.Importantly,photocatalysts can be omitted for many cases,which might involve the electron donor acceptor(EDA)complex.Mechanistic studies indicated benzylic radicals might be involved as the key intermediates.Moreover,the in situ generated NMe3 via cleavage of C–N bond in ammonium salts acts as the electron donor,thus avoiding the use of external-reductant.

关键词： reductive cross coupling visible light external-reductant-free

Nickel-catalyzed reductive coupling of glucosyl halides with aryl/vinyl halides enabling β-selective preparation of C-aryl/vinyl glucosides

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Science China Chemistry 2019年第11期62卷 1492-1496页

作者： JiANDong Liu Chuanhu Lei Hegui Gong School of Materials Science and Engineering Center for Supramolecular Chemistry and Catalysis Department of ChemistryShanghai University

This work describes stereoselective preparation ofβ-C-aryl/vinyl glucosides via mild Ni-catalyzed reductive arylation and vinylation of C1-glucosyl halides with aryl and vinyl halides.A broad range of aryl halides and vinyl halides were employed to yield C-aryl/vinyl glucosides in 42%–93%yields.Good to excellentβ-selectivities were obtained for C-glucosides by using tridentate ligand.

关键词： nickel-catalyzed reductive coupling β-selective preparation C-aryl/vinyl glucosides

Glucose-6-phosphate dehydrogenase neutralizes stresses by supporting reductive glutamine metabolism and AMPK activation

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Signal Transduction and Targeted Therapy 2021年第3期6卷 580-583页

作者： Benfu Zhong Dewei Jiang Yang Hong Lifang Li Li Qiu Ronghui Yang Xiaohan Jin Yawen Song Ceshi Chen Binghui Li Department of Cancer Cell Biology and National Clinical Research Center for Cancer Tianjin Medical University Cancer Institute and HospitalTianjin 300060P.R.China Department of Biochemistry and Molecular Biology Capital Medical UniversityBeijing 100069P.R.China Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences and Yunnan Province Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223China

Dear Editor,Glucose-6-phosphate dehydrogenase(G6PD)is the rate-limiting enzyme in the oxidative pentose phosphate pathway(oxPPP)that can generate cytosolic NADPH(Fig.1a)for biosynthesis and oxidative defence.Here,we reveal a previously unidentified function of G6PD.It,even the natural G6PD deficiency-associated mutant without the activity to maintain the normal oxPPP,can antagonize the stresses by supporting the reductive glutamine metabolism and AMPK activation,independently of the NADPH generation by the oxPPP.

关键词： supporting reductive oxidative

Non-naturally reductive Einstein metrics on Sp(n)

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Frontiers of Mathematics in China 2020年第1期15卷 47-55页

作者： Zhiqi CHEN Huibin CHEN School of Mathematical Sciences Nankai UniversityTianjin 300071China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023China

We prove that Sp(2k+l)admits at least two non-naturally reductive Einstein metrics which are Ad(Sp(k)×Sp(k)×Sp(l))-invariant ifk<1.It implies that every compact simple Lie group Sp(n)for n≥4 admits at least 2[(n-1)... 详细信息

We prove that Sp(2k+l)admits at least two non-naturally reductive Einstein metrics which are Ad(Sp(k)×Sp(k)×Sp(l))-invariant ifkreductive left-invariant Einstein metrics.

关键词： Einstein metric non-naturally reductive metric Riemannian manifold Lie group

Regioselectivity of Pd-catalyzed o-carboranearylation: a theoretical view

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Organic Chemistry Frontiers 2022年第6期9卷 1686-1695页

作者： Jiying Liu Dongmin Fu Zitong Chen Tiantian Li Ling-Bo Qu Shi-Jun Li Wenjing Zhang Yu Lan Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan 450001China School of Chemistry and Chemical Engineering and Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030China

The mechanism and the regioselectivity of Pd-catalyzed B(4)–H arylation and B(4,5)–H diarylation foro-carborane with bidentate directing groups were investigated. The complete catalytic cycle involves Pdmediated concerted metalation–deprotonation, oxidative addition, counterion exchange, and reductiveelimination, where counterion exchange is critical. The reductive elimination is the rate- and regioselectivity-determining step for the whole catalytic cycle. B(3)-Arylation is unfavorable because the stericrepulsion between the substituent group on C(2) and the metal moiety would lead to significant distortionof o-carborane and would result in a higher activation energy for reductive elimination. The distortion ofo-carborane can be clearly observed from the change of its aromaticity in the corresponding transitionstates by the calculation of nucleus-independent chemical shifts. Moreover, counterion exchange withcarboxylate before reductive elimination significantly increases the positive charge of palladium, whichleads to a lower activation free energy for the sequential step.

关键词： elimination catalyzed reductive

reductive Amination with [<sup>11</sup>C]Formaldehyde: A Versatile Approach to Radiomethylation of Amines

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International Journal of Organic Chemistry 2012年第3期2卷 202-223页

作者： Chunying Wu Ruoshi Li Dorr Dearborn Yanming Wang Division of Radiopharmaceutical Science Case Center for Imaging Research Department of Radiology Cleveland USA Environmental Health Case Western Reserve University Cleveland USA

Carbon-11 radiolabeled amines constitute a very important class of radioligands that are widely used for positron emission tomography (PET) imaging. Radiolabeling of amines is often achieved through radiomethylation using [11C]CH3I or [11C]CH3OTf under basic conditions in a strictly anhydrous environment. Functional groups such as hydroxyl and carboxyl groups that are often present in the molecules are normally base sensitive and require protection and deprotection, which substantially prolongs and complicates the radiolabeling process. Here we report a versatile approach to a series of C-11 radiolabeled amines prepared through reductive amination using [11C]formaldehyde. Using a variety of substrates bearing different functional groups, we demonstrate the general utility of this method. In contrast to conventional radiomethylation methods, the reductive amination using [11C]formaldehyde can be carried out in an aqueous environment relatively quickly without the need of protection of base-sensitive functional groups.

关键词： C-11 Formaldehyde Radiomethylation reductive Amination Positron Emission Tomography Radiolabelling

Preparation of 2,5-Bis(Aminomethyl)Furan by Direct reductive Amination of 2,5-Diformylfuran over Nickel-Raney Catalysts

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Green and Sustainable Chemistry 2015年第3期5卷 115-127页

作者： Ngoc-Thuc Le Areum Byun Yohan Han Kee-In Lee Hyungrok Kim Center for Nanocatalysts Green Chemistry and Engineering Division Korea Research Institute of Chemical Technology (KRICT) Daejeon Korea Department of Green Chemistry and Environmental Biotechnology Korea University of Science and Technology (UST) Daejeon Korea

The direct reductive amination of 2,5-diformylfuran (DFF) with ammonia to 2,5-bis(aminomethyl)furan (BAF) was demonstrated, for the first time, over the commercial type Nickel-Raney and acid treated Nickel-Raney catalysts. The effects of reaction parameters such as reaction medium, temperature and hydrogen pressure were described. The acid treated Nickel-Raney catalyst exhibited the highest BAF yield in the THF-water mixed reaction medium. The relatively higher Ni0 species composition and larger surface area of the acid treated Nickel-Raney catalyst with specific reaction conditions contributed greatly to the BAF formation. The oligomeric species, such as furanic imine trimers and tetramers confirmed by MALDI-MS analysis were presented as the intermediates of DFF reductive amination.

关键词： reductive Amination Primary Amine 2 5-Bis(Aminomethyl)Furan 5-Diformylfuran Nickel Raney Catalyst