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Synthesis and Crystal Structure of the Derivative of Hydroquinone from Mannich Reaction 被引量:1
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作者 马朋高 张明杰 +1 位作者 杨启超 于九皋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第3期311-314,共4页
The regioselective Mannich-type aminomethylation of hydroquinone afforded a nitrogen-containing compound, 2,5-bis-(morpholinomethyl)hydroquinone A, and its crystal structure was determined by single-crystal X-ray di... The regioselective Mannich-type aminomethylation of hydroquinone afforded a nitrogen-containing compound, 2,5-bis-(morpholinomethyl)hydroquinone A, and its crystal structure was determined by single-crystal X-ray diffraction. Crystal data for A: C16H24N2O4, Mr = 308.37, orthorhombic, space group Pbca, a = 10.479(4), b = 10.298(4), c = 14.865(5) ?, V = 1604.3(11) ?3, Z = 4, Dc = 1.277 g/cm3, F(000) = 664, μ = 0.092 mm-1, GOF = 1.078, the final R = 0.0508 and wR = 0.1075 for 1416 observed reflections with I > 2σ(I). There exist two intramolecular O–H…N hy- drogen bonds between the phenolic O atoms and the morpholine N donors and the morpholino rings assume the preferred chair conformation. 展开更多
关键词 Mannich reactions PHENOLS AMINOMETHYLATION crystal structure
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Morphology-dependent structures and catalytic performances of Au nanostructures on Cu_2O nanocrystals synthesized by galvanic replacement reaction 被引量:2
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作者 Zhenhua Zhang Rui Song +1 位作者 Tian Cao Weixin Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期1086-1091,共6页
Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Micro... Au nanostructures were prepared on uniform Cu2O octahedra and rhombic dodecahedra via the galvanic replacement reaction between HAuCl 4 and Cu2O. The compositions and structures were studied by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), High-Resolution Transmission Electron Microscope (HRTEM), X-Ray Diffraction (XRD), X-Ray Absorption Spectroscopy (XAS), X-ray Photoelectron Spectroscopy (XPS) and in-situ DRIFTS spectroscopy of CO adsorption. Different from the formation of Au-Cu alloys on Cu2O cubes by the galvanic replacement reaction (ChemNanoMat 2 (2016) 861-865), metallic Au particles and positively-charged Au clusters form on Cu2O octahedra and rhombic dodecahedra at very small Au loadings and only metallic Au particles form at large Au loadings. Metallic Au particles on Cu2O octahedra and rhombic dodecahedra are more active in catalyzing the liquid phase aerobic oxidation reaction of benzyl alcohol than positively-charged Au clusters. These results demonstrate an obvious morphology effect of Cu2O nanocrystals on the liquid-solid interfacial reactions and prove oxide morphology as an effective strategy to tune the surface reactivity and catalytic performance. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 Au/Cu2O nanocomposites Galvanic replacement reaction Liquid-solid interfacial reaction crystal plane effect Aerobic oxidation of benzyl alcohol
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Crystal Structure of a Tricyclic Compound C_(20)H)(28)O_6 Obtained through IMDA Reaction
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作者 CHAI Ji-Jie HE Cun-Heng +3 位作者 LI Ming ZHANG Lu-YanCHEN Shi-Zhi YANG Wen-Qian HUANG Liang(Institute of Materia Medica, Chinese Academy of Medical Sciences & PekingUnion Medical College, No. 1 Xian Nong Tan Street, Beijing 100050) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第5期345-348,共4页
The tricyclic compoun d (2) C20H28O6 has been synthesized through thereaction of IMDA. The crystals of the title compound(2A) were crystallized from etherin monoclinic space group C2 with a unit cell: a = 11. 301 (2),... The tricyclic compoun d (2) C20H28O6 has been synthesized through thereaction of IMDA. The crystals of the title compound(2A) were crystallized from etherin monoclinic space group C2 with a unit cell: a = 11. 301 (2), b=11-.863 (3 ), c =29. 59 (1) , β= 101. 02(5)°, V=3894. 246, Dc=1.2413 g/cm3, Z=8, F(000)=1568, Mr= 364. 00 R=0.055, R2=0. 055, μ= 535 cm-1, S(GOF) =0. 571. Theconfiguration of C2a-H in the title compound was found to be contrary to what wasexpected and a possible mechanism of reaction was proposed. 展开更多
关键词 IMDA reaction crystal structure TRICYCLIC COMPOUND
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Effect of Copper (II) Ions on Quality of Struvite Produced in Continuous Reaction Crystallization Process at the Magnesium Ions Excess 被引量:1
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作者 Nina Hutnik Boguslawa Wierzbowska +1 位作者 Krzysztof Piotrowski Andrzej Matynia 《Advances in Chemical Engineering and Science》 2013年第4期1-6,共6页
The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions ad... The research results concerning continuous removal of phosphate (V) ions from solutions containing 1.0 or 0.20 mass % of phosphate (V) ions and 0.2 or 0.5 mg/kg of copper (II) ions using magnesium and ammonium ions addition are presented. Continuous reaction crystallization of struvite MgNH4PO4 × 6H2O ran both under stoichiometric conditions and at 20% excess of magnesium ions (pH 9, t 900 s). It was concluded, that presence of copper (II) ions in a process system influenced product quality moderately advantageously. Mean size of struvite crystals enlarged by ca. 6% only. Lower concentration of phosphate (V) ions and excess of magnesium ions caused, that products of ca. 9% - 13% larger crystal mean size (up to ca.40mm) were removed from the crystallizer. Presence of struvite crystals and copper (II) hydroxide were detected analytically in the products (Cu in a product varied from 6 to 90 mg/kg). Presence of copper (II) ions favored crystallization of struvite in the form of tubular crystals. 展开更多
关键词 Struvite Phosphate(V) IONS COPPER IONS CONTINUOUS reaction crystallization DT MSMPR crystalLIZER crystal Size Distribution Product QUALITY
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Continuous Reaction Crystallization of Struvite in a DTM Type Crystallizer With Jet Pump of Ascending Suspension Flow in a Mixing Chamber–Kinetic Approach of the Process
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作者 Agata Mazienczuk Andrzej Matynia +1 位作者 Krzysztof Piotrowski Boguslawa Wierzbowska 《Journal of Crystallization Process and Technology》 2012年第3期96-104,共9页
Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystall... Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s. 展开更多
关键词 STRUVITE crystal Size Distribution (CSD) reaction crystallization Kinetics CONTINUOUS DTM TYPE crystalLIZER Jet Pump
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Crystal Structure of Derivative of H_4′-NOBIN and the Applications in Hetero-Diels-Alder Reaction
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作者 牧初春 李新生 徐东成 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第2期205-209,共5页
Novel Schiff bases of H4'-NOBIN 5a and 5b were synthesized by condensation of 3 with aldehydes. Compound 5b was structurally characterized by single-crystal X-ray diffraction. The asymmetric hetero-Diels-Alder reacti... Novel Schiff bases of H4'-NOBIN 5a and 5b were synthesized by condensation of 3 with aldehydes. Compound 5b was structurally characterized by single-crystal X-ray diffraction. The asymmetric hetero-Diels-Alder reactions were carried out with high yields and good enantioselectivities in the presence of Ti-(S)-5a complex as catalyst. Crystallographic data for 5b: C27H22BrNO, Mr = 456.37, triclinic, space group P1 with a = 9.1618(2), b = 10.3836(2), c = 12.7718(2) А,α=105.4860(10),β= 94.6360(10), γ= 108.4610(10)°, V= 1092.32(4)А^3, Z=2, Dc= 1.388 g/cm^3, μ= 1.900 mm^-1, F(000) = 468, R = 0.0476 and wR = 0.1248 for 3092 observed reflections (I〉 2σ(I)). 展开更多
关键词 crystal structure BINOL derivative Schiff bases Diels-Alder reactions
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The Crystal Structure Study of CaSrFe0.75Co0.75Mn0.5O6−δ by Neutron Diffraction
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作者 Amara Martinson Mandy Guinn Ram Krishna Hona 《Journal of Materials Science and Chemical Engineering》 2024年第1期29-35,共7页
The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The... The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The material is synthesized using a solid-state synthesis method at a temperature of 1200˚C. Neutron diffraction data is subjected to Rietveld refinement, and a comparative analysis with X-ray diffraction (XRD) data is performed to unravel the structural details of the material. The findings reveal that the synthesized material exhibits a cubic crystal structure with a Pm-3m phase. The neutron diffraction results offer valuable insights into the arrangement of atoms within the lattice, contributing to a comprehensive understanding of the material’s structural properties. This research enhances our knowledge of CaSrFe0.75</sub>Co0.75</sub>Mn0.5</sub>O6−δ</sub>, with potential implications for its applications in various technological and scientific domains. 展开更多
关键词 XRD Neutron Diffraction Perovskite Oxides crystal Structure Solid-State reaction
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Synthesis and Crystal Structure of a N,N,N′-tri(2-hydroxy-5-methylbenzyl)-1,2-ethanediamine 被引量:2
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作者 王暖升 汪永涛 +1 位作者 李俊英 李天铎 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1533-1536,共4页
An aminophenol ligand, N,N,N'-tri(2-hydroxy-5-methylbenzyl)-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The titl... An aminophenol ligand, N,N,N'-tri(2-hydroxy-5-methylbenzyl)-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The title compound (C26H32N2O3, Mr = 420.54) belongs to the monoclinic system, space group P21/n with a = 8.6233(14), b = 10.2655(16), c = 26.017(4) A, β = 95.797(2)°, V = 2291.3(6) A^3, Z = 4, the final R = 0.0461 and wR = 0.1139 for 4267 unique reflections (Rint = 0.028) with 11691 observed ones (I〉 2a(I)). 展开更多
关键词 Mannich reaction aminophenol ligand crystal structure Mannich reaction aminophenol ligand crystal structure
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Synthesis and Crystal Structure of α-( N-Protected a mino)β-lactam Derivative of 1 ,5-Benzothiazepine 被引量:2
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作者 李媛 金声 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第5期331-334,共4页
The crystal of the title compound C, C 30 H 30 N 2O 3S has been prepared by reaction of 1,5 benzothiazepine with N protected glycine and determined by X ray single crystal diffraction. Crystal data:... The crystal of the title compound C, C 30 H 30 N 2O 3S has been prepared by reaction of 1,5 benzothiazepine with N protected glycine and determined by X ray single crystal diffraction. Crystal data: M r =498.62, triclinic with P 1 space group, a=10.880(2), b=13.955(3), c=9.537(2), α=99.34(3)°, β=110.43(3)°, γ=88 56(3)°, V=1338.2(5) 3, F(000)=528, λ (Mo Kα)=0.71073, Z=2, D c =1 237g/cm 3, μ =0.154mm -1 . Final R=0.0453, wR =0.1256 for 3491 observed reflections 〔 I>2σ(I) 〕. Structure analysis reveals that the substituents at C(23) and C(7) in four membered ring are located on the same side. The conformation of seven membered ring is chair like. 展开更多
关键词 crystal structure cycloaddition reaction β lactam 1 5 benzothiazepine.
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Syntheses and Crystal Structures of Cd(Ⅱ) and Ni(Ⅱ) Complexes Containing Flexible Sulfide and Nitrogen Heterocyclic Ligands 被引量:3
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作者 郝晓敏 谷长生 +3 位作者 韩丝银 苗艳丽 李泳 宋文东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期408-416,共9页
Two new coordination polymers [Cd(EBLA)(ip)(H2O)] (1) and [Ni(EBSA) (im)2(H2O)], (2) were synthesized by hydrothermal and solution methods using 2,2'-dithio- salicylicacid (EBSA), lH-imidazo[4,5-f][... Two new coordination polymers [Cd(EBLA)(ip)(H2O)] (1) and [Ni(EBSA) (im)2(H2O)], (2) were synthesized by hydrothermal and solution methods using 2,2'-dithio- salicylicacid (EBSA), lH-imidazo[4,5-f][1,10]phenanthroline (ip), imidazole (im), Cd(NO3)2-4H2O and Ni(NOa)z'6H20. The complexes were characterized by elemental analysis and FT-IR. Meanwhile, the crystal structures, fluorescence properties of complex 1 and thermogravimetrie analysis of complex 2 have been studied. In complex 1, 2,2'-dicarboxydiphenylthioether (EBLA) was prepared with 2,2'-dithiosalicylicacid (EBSA) in situ reaction by hydrothermal method. Complex 1 is a dinuclear structure and Cd2+ is five-coordinated in a distorted trigonal bipyramidal geometry. Complex 2 is a one-dimensional infinite linear chain and Ni2+ is six-coordinated to form a distorted octahedral geometry. Hydrogen bonding and π-π interactions are observed in these complexes. 展开更多
关键词 2 2'-dithiosalicylicacid in situ reaction crystal structure
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Syntheses and Crystal Structures of Two AlxRE3(Si1-yAly)S7(RE=Sm and Gd)Compounds 被引量:2
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作者 迟洋 郭胜平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第3期341-347,共7页
Two new quaternary rare-earth chalcogenides,Al_(0.42)Sm_3(Si_(0.74)Al_(0.26))S_7(1) and Al_(0.38)Gd_3(Si_(0.86)Al_(0.14))S_7(2),have been synthesized by a facile solid-state route with boron as the... Two new quaternary rare-earth chalcogenides,Al_(0.42)Sm_3(Si_(0.74)Al_(0.26))S_7(1) and Al_(0.38)Gd_3(Si_(0.86)Al_(0.14))S_7(2),have been synthesized by a facile solid-state route with boron as the reducing reagent.They crystallize in the noncentrosymmetric hexagonal space group P6_3,belonging to the Ce_6Al_(3.33)S_(14) structure-type.Their 3-D structures feature 3-D frameworks constructed by RES_8 bicapped trigonal prisms,and Al and Si occupy the octahedral and tetrahedral voids,respectively.Al(2) and Si(1) co-occupying the 2b site and Al(1) partially occupying the 2a site have to be considered for the stability of the structures and charge balances.The Ce_6Al_(3.33)S_(14) structure-type compounds with their rich compositions and traits are discussed.The diffuse reflectance spectrum measurement of 2 indicates that it has an energy gap of 2.13 eV. 展开更多
关键词 rare-earth chalcogenides solid-state reaction crystal structure energy gap
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Electrochemical CO2 reduction over nitrogen-doped SnO2 crystal surfaces 被引量:3
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作者 Yuefeng Zhang Jianjun Liu +3 位作者 Zengxi Wei Quanhui Liu Caiyun Wang Jianmin Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第6期22-30,共9页
Crystal planes of a catalyst play crucial role in determining the electrocatalytic performance for CO2 reduction.The catalyst SnO2 can convert CO2 molecules into valuable formic acid(HCOOH).Incorporating heteroatom N ... Crystal planes of a catalyst play crucial role in determining the electrocatalytic performance for CO2 reduction.The catalyst SnO2 can convert CO2 molecules into valuable formic acid(HCOOH).Incorporating heteroatom N into SnO2 further improves its catalytic activity.To understand the mechanism and realize a highly efficient CO2-to-HCOOH conversion,we used density functional theory(DFT)to calculate the free energy of CO2 reduction reactions(CO2RR)on different crystal planes of N-doped SnO2(N-SnO2).The results indicate that N-SnO2 lowered the activation energy of intermediates leading to a better catalytic performance than pure SnO2.We also discovered that the N-Sn O2 (211)plane possesses the most suitable free energy during the reduction process,exhibiting the best catalytic ability for the CO2-to-HCOOH conversion.The intermediate of CO2RR on N-SnO2 is HCOO*or COOH* instead of OCHO*.These results may provide useful insights into the mechanism of CO2RR,and promote the development of heteroatomdoped catalyst for efficient CO2RR. 展开更多
关键词 CO2 REDUCTION reaction SNO2 crystal surface ELECTROCATALYSIS First PRINCIPLES
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Synthesis,Crystal Structure,Physical Properties and Theoretical Studies of the New Ternary Sulfide with Closed Cavities:CsYb_7S_(11) 被引量:2
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作者 郑宇君 刘鹏飞 +2 位作者 吴新涛 吴立明 林华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第11期1780-1790,共11页
A novel ternary rare-earth sulfide, CsYb7S(11), has been successfully synthesized by high-temperature solid-state reaction of an elemental mixture with modified Cs Cl flux. The single-crystal X-ray diffraction data ... A novel ternary rare-earth sulfide, CsYb7S(11), has been successfully synthesized by high-temperature solid-state reaction of an elemental mixture with modified Cs Cl flux. The single-crystal X-ray diffraction data reveal its orthorhombic symmetry in space group Cmca(no. 64) with a = 15.271(3), b = 13.414(2), c = 18.869(3) A°, V = 3865.2(2) A°^3, Z = 8, Mr = 1696.85, Dc = 5.832 g/cm^3, μ = 36.538 mm^-1, F(000) = 5768, the final R = 0.0225 and w R = 0.0517 for 2258 observed reflections with I 〉 2σ(I), 2.67〈θ〈27.48o, w = 1/[σ^2(Fo^2) +(0.0443 P)2 + 8.7453 P], where P =(Fo^2 + 2Fc^2)/3, S = 1.036,(Δρ)max = 1.609 and(Δρ)min = –1.922. The remarkable structural feature is the dual tricapped Cs2@S18 cube closed cavities far apart within the three-dimensional [Yb7S(11)]-covalent bonding matrix. Magnetic susceptibility measurements show that the title compound exhibits temperature-dependent(50~300 K) para-magnetism and obey the Curie-Weiss law. Moreover, the optical gap of 2.03 Ev for CsYb7S11 was deduced from the UV/Vis reflectance spectroscopy and DFT study indicates an indirect band gap with an electronic transfer excitation of S-3p to Yb-5d orbital. 展开更多
关键词 rare-earth sulfide high-temperature solid-state reaction crystal structure magnetic property optical band gap
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Synthesis, Crystal Structure and Property of Cu Pb_2(OH)_2Cl_3 被引量:1
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作者 黄荣荣 张素允 +2 位作者 崔美艳 徐军 何长振 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第4期594-598,共5页
A new copper(1)-lead(Ⅱ) oxyhalide, CuPb2(OH)2Cl3, has been prepared by hydrothermal reaction and structurally characterized by single-crystal X-ray analysis. The compound crystallizes in tetragonal, space group... A new copper(1)-lead(Ⅱ) oxyhalide, CuPb2(OH)2Cl3, has been prepared by hydrothermal reaction and structurally characterized by single-crystal X-ray analysis. The compound crystallizes in tetragonal, space group 14(1)/acd with a = b = 13.77(1), c = 15.38(1) A, V = 2916.2(2), Z = 4, Mr = 618.29, Dc = 5.633 g/cm^3,μ = 49.97(2) mm^-1, F(000) = 4192, the final R = 0.0204 and wR = 0.0452 for 757 observed reflections with I 〉 2σ(I). The structure of CuPb2(OH)2Cl3 contains one-dimensional helical chains built by CuCl4 tetrahedra with comer-sharing along the c-axis, in which the Pb^2+ and OH^- ions are located at the voids between chains. Optical reflectance spectrum measurements indicate that it is a semiconductor with a band-gap of 3.23 eV. 展开更多
关键词 oxyhalide crystal structure hydrothermal reaction SEMICONDUCTOR
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Synthesis, Crystal Structure and Catalytic Activity of a Dinuclear Aluminum Alkyl Complex 被引量:1
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作者 WEI Yun ZHOU Shuang-Liu WANG Shao-Wu 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第2期307-312,共6页
Treatment of indolyl-3-aldimines(3-~tBuN=CH)C8H5NH with AlMe3 afforded the deprotonated indolyl aluminum complex cis-[(μ-η~1:η~1-3-~tBuN=CH)C8H5NAlMe2]2,and its crystal structure was determined by X-ray single... Treatment of indolyl-3-aldimines(3-~tBuN=CH)C8H5NH with AlMe3 afforded the deprotonated indolyl aluminum complex cis-[(μ-η~1:η~1-3-~tBuN=CH)C8H5NAlMe2]2,and its crystal structure was determined by X-ray single-crystal diffraction.The crystal belongs to the orthorhombic system,space group P21212 with a = 14.590(9),b = 15.860(2),c = 13.266(8) A,μ=0.118 mm^(-1),Mr = 512.64,V= 3069.5(3) A^3,Z = 4,Dc= 1.109 g/cm^3,F(000) = 1104,R= 0.0451 and wR = 0.0937 for 4978 observed reflections with I 2σ(I).In addition,the title compound exhibited a high catalytic activity toward the addition of amines to carbodiimide to form guanidines. 展开更多
关键词 INDOLE organoaluminum crystal structure guanylation reaction
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Synthesis and Crystal Structure of a New Quaternary Sulfide FeSm6Si2S14 被引量:1
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作者 孙岳玲 迟洋 郭胜平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第9期1369-1375,共7页
One new quaternary rare-earth sulfide, FeSm6Si2S(14), has been synthesized by a facile solid-state route with boron as the reducing reagent. It crystallizes in the noncentrosymmetric hexagonal space group P63, belon... One new quaternary rare-earth sulfide, FeSm6Si2S(14), has been synthesized by a facile solid-state route with boron as the reducing reagent. It crystallizes in the noncentrosymmetric hexagonal space group P63, belonging to the Ce6Al(3.33)S(14) structure-type, and the AxRE3MQ7 family. Its crystal structure features a 3-D framework constructed by SmS 8 bicapped trigonal prisms, where Fe and Si atoms occupy the octahedral(2a) and tetrahedral(2c) voids, respectively. The FeS 6 octahedra are connected with each other to form a chain along the b direction. FeSm6Si2S(14) represents a new chemical composition among the large family of AxRE3MQ7 compounds. The other related compounds containing transition metal are also discussed. 展开更多
关键词 rare-earth sulfide solid-state reaction crystal structure AxRE3MQ7 family compounds
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Synthesis,Crystal Structure,and Optical Property of Zero-dimensional Quaternary Thioborate:Ba9B3GaS15 被引量:1
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作者 王金秋 刘鹏飞 +1 位作者 黎艳艳 吴立明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第12期1860-1867,共8页
A new zero-dimensional(0D) thioborate Ba_9B_3GaS_(15) has been discovered by conventional high-temperature solid-state reaction. The compound crystallizes in orthorhombic space group Pbca with a = 8.4759(8),b = ... A new zero-dimensional(0D) thioborate Ba_9B_3GaS_(15) has been discovered by conventional high-temperature solid-state reaction. The compound crystallizes in orthorhombic space group Pbca with a = 8.4759(8),b = 22.266(2),c = 31.426(3) ?,V = 5931(2) ?~3,Z = 8,Mr = 1819.11,Dc = 4.075 g/cm3,μ = 13.684 mm^(-1),F(000) = 6320,S = 1.034,(Δρ)max = 5.039,(Δρ)min = –5.409 e/?~3,the final R = 0.0362 and w R = 0.1053 for 19243 observed reflections with I 〉 2σ(I). The structure is constructed by discrete [BS_3]^(3–) trigonal planes and isolated [GaS_4]^(5–) tetrahedra with Ba^(2+) and isolated S^(2–) filled among them. The UV-Vis-near-IR spectrum reveals a wide band gap of 3.15 eV that agrees with the electronic structure calculation. 展开更多
关键词 thioborate high-temperature solid-state reaction crystal structure optical band gap electronic structure calculation
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6,8-Di-tert-butyl-3-(2,4-dimethyl-quinolin-7-yl)-3,4-dihydro-2H-benzo[e][1,3]oxazine: Synthesis, Crystal Structure and Luminescent Properties 被引量:1
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作者 苏清 赵天琦 +3 位作者 张杰 李佩 赵晴 叶玲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第2期237-243,共7页
6,8-Di-tert-butyl-3-(2,4-dimethyl-quinolin-7-yl)-3,4-dihydro-2H-benzo[e][1,3]oxa- zine(1) was obtained by one-pot reaction starting from 2,4-di-tert-butylphenol, 7-amino-2,4- dimethyl-quinoline and paraformaldehyd... 6,8-Di-tert-butyl-3-(2,4-dimethyl-quinolin-7-yl)-3,4-dihydro-2H-benzo[e][1,3]oxa- zine(1) was obtained by one-pot reaction starting from 2,4-di-tert-butylphenol, 7-amino-2,4- dimethyl-quinoline and paraformaldehyde. The compound was structurally characterized by NMR, IR and single-crystal X-ray diffraction along with the elemental analysis. Compound 1 crystallizes as solvate with chloroform. The solvate 1·CHCl3(C28 H35 Cl3 N2 O, Mr = 521.93) belongs to the triclinic system, space group P1 with a = 10.852(2), b = 11.352(2), c = 13.050(3), α = 101.95(3), β = 92.94(3), γ = 114.64(3)o, V = 1412.4(5)3, Z = 2, Dc = 1.227 g/cm3, F(000) = 552, μ = 0.347 mm–1, R = 0.0959 and wR = 0.2725(I 〉 2?(I)). The chloroform molecule displays a rotational disorder as one chloro atom can be located at two different positions. The packing of 1·CHCl3 was further stabilized by intramolecular C–H…O interactions, intermolecular C–H…N interactions, C–H…π interactions, and π…nteractions. The luminescent properties of compound 1 in both methylene chloride solution and the solid state were studied. 展开更多
关键词 Mannich reaction crystal structure quinolinederivatives SYNTHESIS luminescent properties
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One-pot Synthesis,Crystal Structures and Antimicrobial Activities of Two New 1,4-Disubstituted 1,2,3-Triazole-4-Carboxylates 被引量:2
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作者 MUHAMMAD Naeem Ahmed KHAWAJA Ansar Yasin +2 位作者 MUHAMMAD Nawaz Tahir IFZAN Arshad MURTAZA Madni 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第1期26-32,共7页
Two new 1,4-disubstituted 1,2,3-triazoles-4-carboxylates were synthesized via click reaction. Compound 1a was synthesized by the interaction of 6-nitro-tetrazolo[1.5-a]-pyridine with ethyl propynoate at room temperatu... Two new 1,4-disubstituted 1,2,3-triazoles-4-carboxylates were synthesized via click reaction. Compound 1a was synthesized by the interaction of 6-nitro-tetrazolo[1.5-a]-pyridine with ethyl propynoate at room temperature in the presence of Cu(OAc)2 as a catalyst and THF as solvent. Compound 1b was also synthesized by the same manner except that tert-butyl propionate, instead of ethyl propynoate, was used. The compounds were characterized by IR, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction analysis. Compound 1a(C10H9N5O4) crystallizes in the triclinic system, space group P1 with a = 5.0894(9), b = 8.9834(13), c = 13.089(2) ?, α= 83.041(7), β= 80.256(7), γ=87.296(8)°, V = 585.24(16)?3, Z = 2, Mr = 263.22, crystal size(mm) = 0.37 × 0.20 ×0.18,(I 〉 2σ(I)) = 8557, 2493, 1229, Rint = 0.057. Compound 1b(C12H13N5O4) crystallizes in the monoclinic system, space group P21/c with a = 6.8854(5), b = 21.783(2), c = 9.3986(8) ?,β = 93.239(4)°, V = 1407.4(2)?3, Z = 4, Mr = 291.27, crystal size(mm) = 0.38 × 0.22 × 0.20,(I 〉 2σ(I)) = 11842, 3172, 1866, Rint = 0.047. Antimicrobial assay results showed that the title compounds display excellent activities to different bacterial and fungal strains. 展开更多
关键词 click reaction TRIAZOLES crystal structure antimicrobial activity
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Synthesis and Crystal Structure of a Novel 14,20-Annulated Pentacyclic Steroid 17(S)-Methyl-13β-hydroxyl-14(R),20(S)-epoxy-pregn-4-en-3-one 被引量:1
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作者 冯书晓 梁政勇 章亚东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第1期77-81,共5页
The title compound 17(S)-methyl-13β-hydroxyl-14(R),20(S)-epoxy-pregn-4-en-3-one was synthesized by an improved tandem reaction, and its structure was determined by IR, NMR, HR MS and X-ray single-crystal diffra... The title compound 17(S)-methyl-13β-hydroxyl-14(R),20(S)-epoxy-pregn-4-en-3-one was synthesized by an improved tandem reaction, and its structure was determined by IR, NMR, HR MS and X-ray single-crystal diffraction. The crystal belongs to orthorhombic, space group P212121 with a = 10.55248(15), b = 12.14700(16), c = 14.56841(18) ?, V = 1867.39(4) ?3, Z = 4, Dc= 1.175 g/cm3, μ= 0.604 mm-1, F(000) = 720, the final R = 0.0400 and w R = 0.1072 for 3610 observed reflections with I 〉 2σ(I). 展开更多
关键词 synthesis pentacyclic steroid crystal structure tandem reaction
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