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A pyrazine-Based 2D Conductive Metal-Organic Framework for Efficient Lithium Storage

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中国化学:英文版 2023年第14期41卷 1691-1696页

作者： Xiaoxiao Sun Xiaoli Yan Keming Song Ting Zhang Zongfan Yang Xi Su Weihua Chen Long Chen Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistryTianjin UniversityTianjin300072 China College of Chemistry and Green Catalysis Center Zhengzhou UniversityZhengzhouHenan450001 China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchunJilin130012 China

The merits of intrinsic electrical conductivity, high specific surface area, tunable chemical composition and tailor-made properties enable two-dimensional conductive metal-organic frameworks (2D c-MOFs) as promising next-generation electrode materials in the field of energy storage and conversion. Herein, we have designed and synthesized a novel pyrazine-based 2D c-MOF (TPQG-Cu-MOF) bearing extended π-conjugated structure and abundant redox active sites. Thanks to the excellent redox reversibility of pyrazine units and CuO2 units, as well as the insolubility of the rigid framework skeleton, TPQG-Cu-MOF as the cathode material of lithium-ion battery exhibits a reversible specific capacity (150.2 mAh·g–1 at 20 mAh·g–1), good cycling stability (capacity retention of 82.6% after 500 cycles at 1 A·g–1) and excellent rate performance. Comprehensive ex-situ spectroscopic studies revealed the reversible redox activity of pyrazine units and CuO2 units of TPQG-Cu-MOF during the Li+ insertion/extraction process. The deepening fundamental understanding of the structure-property relationship was proposed, which might pave the way for further development of efficient MOF-based energy storage devices.

关键词： Two-dimensional Conductive metal-organic frameworks pyrazine Energy storage Lithium-ion battery Cathode Stability ComprehensiveSummary

Pb（NO3）2 Mediated Synthesis of pyrazine

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Chinese Journal of Chemistry 2007年第1期25卷 105-107页

作者： KOTHARKAR, Sandeep Anilrao SHINDE, Devanand Baburao Department of Chemical Technology Dr Babasaheb Ambedkar Marathwada University Aurangabad (M.S.)-431004 India

Lead nitrate was used as an efficient catalyst in the oxidation and condensation reaction of hydroxy ketone with diamine leading to the formation of pyrazine derivatives in excellent yields.

关键词： Pb（NO3）2 pyrazine aromatization

Hydrothermal Synthesis and Structure of [(PbCl_2)(μ-Pyz)_(1/2)]_n (Pyz = pyrazine)

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Chinese Journal of Structural Chemistry 2006年第4期25卷 789-792页

作者： LIAO Qiu-Xia ZHANG Jian QIN Ye-Yan YAO Yuan-Gen State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A novel 2-D lead-containing hybrid compound, [（PbCl2）（μ-Pyz）1/2], （Pyz = pyrazine） 1, has been synthesized by the hydrothermal assembly of pyrazine with lead chloride. Elemental analysis and X-ray crystal structure analyses were carded out for the structural determination and characterization of the title compound. Compound 1 crystallizes in orthorhombic, space group lbam, with a = 19.5558（18）, b = 7.1939（6）, c = 7.5449（6） A, V = 1061.44（16） .A^3, C2H2Cl2NPb, Mr= 318.14, Z = 8, Dc= 3.982 g/cm^3, μ = 32.63 mm^-1, F（000） = 1096.0, R = 0.0368 and wR = 0.0901 for 623 observed reflections （I 〉 2σ（I））.

关键词： crystal structure lead chloride pyrazine

Antifungal Evaluation of Copper(Ⅱ) Complex from a Schiff Base Derivative of pyrazine on Schizosaccharomyces pombe

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Chinese Journal of Structural Chemistry 2019年第1期38卷 95-102,4页

作者：杨平 School of Environment Jinan University

A new copper(Ⅱ) complex of CuLCl_2, where L = N^1-(1-pyrazin-2-yl-ethylidene)-ethane-1,2-diamine, a tridentate Schiff base derived from 2-acetylpyrazine has been prepared. The complex has been characterized by FT-IR, elemental analysis and single-crystal X-ray diffraction studies. Structural studies reveal that CuLCl_2 is a mononuclear copper(Ⅱ) complex with distorted square pyramidal geometry. Antifungal activity of CuLCl_2 was investigated by use of microcalorimetric measurement system and evaluated against S. pombe. It has high antifungal activity with IC_(50) = 213 μg/mL.

关键词： antifungal agents copper Schiff bases pyrazine S.pombe

Theoretical study on S_1(~1B_(3u)) state electronic structure and absorption spectrum of pyrazine

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Science China Chemistry 2008年第12期51卷 1166-1173页

作者： HE RongXing1, ZHU ChaoYuan 2, CHIN Chih-Hao3 & LIN Sheng-Hsien2,3 1 College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China 2 Department of Applied Chemistry, Institute of Molecular Science and Center for Interdisciplinary Molecular Science, National Chiao-Tung University, Hsinchu 300, China 3 Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, China College of Chemistry and Chemical Engineering Southwest University Chongqing China Department of Applied Chemistry Institute of Molecular Science and Center for Interdisciplinary Molecular Science National Chiao-Tung University Hsinchu China Institute of Atomic and Molecular Sciences Academia Sinica Taipei China

Making use of a set of quantum chemistry methods, the harmonic potential surfaces of the ground state (S0(1Ag)) and the first (S1(1B3u)) excited state of pyrazine are investigated, and the electronic structures of the two states are characterized. In the present study, the conventional quantum mechanical method, taking account of the Born-Oppenheimer adiabatic approximation, is adopted to simulate the absorp-tion spectrum of S1(1B3u) state of pyrazine. The assignment of main vibronic transitions is made for S1(1B3u) state. It is found that the spectral profile is mainly described by the Franck-Condon progression of totally symmetric mode ν6a. For the five totally symmetric modes, the present calculations show that the frequency differences between the ground and the S1(1B3u) state are small. Therefore the displaced harmonic oscillator approximation along with Franck-Condon transition is used to simulate S1(1B3u) absorption spectra. The distortion effect due to the so-called quadratic coupling is demonstrated to be unimportant for the absorption spectrum, except the coupling mode ν10a. The calculated S1(1B3u) ab-sorption spectrum is in reasonable agreement with the experimental spectra.

关键词： pyrazine absorption spectrum quantum mechanical method electronic structure

Synthesis, properties and application of novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis（BF2） fluorescent dyes:BOPYPYs

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Chinese Chemical Letters 2019年第12期30卷 2271-2273页

作者： Xindong Jiang Shuai Yue Kepeng Chen Zhumei Shao Chen Li Yajun Su Jianzhang Zhao College of Applied Chemistry Shenyang University of Chemical TechnologyShenyang 110142China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China Department of Chemistry Graduate School of ScienceHiroshima UniversityHigashi-Hiroshima 739-8526Japan

Novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF2) fluorescent dyes(BOPYPYs) were obtained by reaction of pyrrole-2-carboxaldehyde with 1-(pyrazin-2-yl)hydrazine in the presence of Et3 N-BF3·Et2 O for the first time.The absorption maxima of pyrazine-fused BOPYPY are obviously bathochromic shifts,in contrast to those of the reported BOPPY,indicating that the discrepant substitute groups between pyridine and pyrazine result in the remarkable wavelength difference.The new series of BO PYPYs possess high molar extinction coefficients,high fluorescence quantum yields,and larger Stokes shifts.A Knoevenagel reaction of BOPYPY with 4-dimethylaminobenzaldehyde smoothly produced the dye with the extension of π-conjugation.Dimethylamino-containing BOPYPY as a pH-responsive fluorescent sensor could detect pH value.

关键词： BOPYPY pyrazine Fluorescent dye Unsymmetric pH

Synthesis and structure determination of pyrazine-containing macrocyclic polyazomethines

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Chinese Chemical Letters 2010年第10期21卷 1263-1266页

作者： Liang Chun Wu Long Qing Liu Hai Shan Jin Ming Liang Ma Xiao Li Zhao Ke Wen Division of Supramolecular Chemistry and Medicinal Chemistry Key Laboratory of Brain Functional Genomics MOE and Shanghai Key Laboratory of Brain Functional Genomics East China Normal University Shanghai 200062 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes and Department of Chemistry East China Normal University Shanghai 200062 China

Two pyrazine-containing macrocyclic polyazomethines 2 and 3 were synthesized by direct [2 ＋ 2] and [3 ＋ 3] condensation reactions between 2,21-[pyrazine-2,3-diylbis（oxy）]dibenzaldehyde （1） and hydrazine. Both 2 ... 详细信息

关键词： Azomethine Macrocycles Schiff base pyrazine

Synthesis,Crystal Structure and Luminescence of a Novel One-dimensional Silver(Ⅰ)Sulfonate Complex with pyrazine Ligand

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Chinese Journal of Structural Chemistry 2011年第2期30卷 211-215页

作者：刘海燕迟云超孙红梅 Department of Chemistry and Pharmaceutical Engineering Suihua University

The title complex,[Ag 2 （L1） 2 （Pyr）·2.5H 2 O] 1 （L1=6-amino-1-naphthalenesulfonate anion,Pyr=pyrazine）,has been synthesized and characterized by single-crystal X-ray diffraction analysis.It crystallizes in triclinic,space group P1,with a=7.339（5）,b=13.105（5）,c=14.097（5）,α=84.377（5）,β=76.921（5）,γ=79.628（5）°,V=1296.7（11） 3,C 48 H 50 Ag 4 N 8 O 17 S 4,M r=1570.68,Z=1,D c=2.011 g/cm 3,μ=1.732 mm-1,F（000）=782,S=1.148,the final R=0.0436 and wR=0.1181 for 4130 observer reflections （I 2σ（Ⅰ））.Compound 1 shows a rare one-dimensional （1D） double chain,and the chains are further connected through secondary bonding,hydrogen bonds,and π-π interactions to generate a three-dimensional （3D） supramolecular structure.The luminescent property of 1 was also studied in the solid state at room temperture.

关键词： silver（Ⅰ） sulfonate pyrazine coordination polymer luminescence

Precise Design and Deliberate Tuning of Turn-On Fluorescence in Tetraphenylpyrazine-Based Metal-Organic Frameworks

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Research 2023年第1期2022卷 341-351页

作者： He-Qi Zheng Lin Zhang Mengting Lu Xiaoyan Xiao Yu Yang Yuanjing Cui Guodong Qian State Key Laboratory of Silicon Materials Cyrus Tang Center for Sensor Materials and ApplicationsSchool of Materials Science EngineeringZhejiang UniversityHangzhou 310027China

The manipulation on turn-on fluorescence in solid state materials attracts increasing interests owing to their widespread applications.Herein we report how the nonradiative pathways of tetraphenylpyrazine(TPP)units in metal-organic frameworks(MOFs)systems could be hindered through a topological design approach.Two MOFs single crystals of different topology were constructed via the solvothermal reaction of a TPP-based 4,4',4",4"-(pyrazine-2,3,5,6-tetrayl)tetrabenzoic acid(H,TCPP)ligand and metal cations,and their mechanisms of formation have been explored.Compared with the innate lowfrequency vibrational modes of flu net Tb-TCPP-1,such as phenyl ring torsions and pyrazine twists,Tb-TCPP-2 adopts a shp net,so the dihedral angle of pyrazine ring and phenyl arms is larger,and the center pyrazine ring in TPP unit is coplanar,which hinders the radiationless decay of TPP moieties in Tb-TCPP-2.Thereby Tb-TCPP-2 exhibits a larger blue-shifted fluorescence and a higher fluorescence quantum yield than Tb-TCPP-1,which is consistent with the reduced nonradiative pathways.Furthermore,Density functional theory(DFT)studies also confirmed aforementioned tunable turn-on fluorescence mechanism.Our work constructed TPP-type MOFs based on a deliberately topological design approach,and the precise design of turn-on fluorescence holds promise as a strategy for controlling nonradiative pathways.

关键词： mechanism. pyrazine phenyl