一个二维梯状化合物[Ni(μ1，5-dca)2(en)]n的合成，结构和磁性(英)

A new nickel(Ⅱ)-dicyanamide compound, [Ni(dca)₂(en)]_n (1) (dca=dicyanamide anion, [N(CN)₂]^-); en=ethylene diamine), has been synthesized and its structure has been determined by single crystal X-ray diffraction analysis. The crystal is monoclinic, space group P2₁/n with unit cell dimensions: a=0.694 3(1) nm, b=1.041 5(2) nm, c=1.4132(2) nm, and β=90.381°, Z=4, V=1.011 0(3) nm³. In this compound, the adjacent nickel atoms are connected by dca all in μ_1，5-bridging mode to form ladder-like units, which are linked with double dca bridges to generate a regular infinite stair-like structure. Temperature-dependent magnetic susceptibility was also characterized for this compound. CCDC: 208276.     

Synthesis and Crystal Structure of a New Coordination Polymer: {[AgL]ClO_4}_n(L = 2,5-Bis(3-pyridinylmethylthio)-l,3,4-thiadiazole)

The title complex {[AgL]ClO4}n(L=2,5-bis(3-pyridinylmethylthio)-1,3,4-thiadiazole) was synthesized by the reaction of Ag(I) salt and a novel flexible ligand L.Its structure was determined by X-ray crystallography with the following data:monoclinic,space group P21/n,a=16.5068(13),b=7.6548(4),c=16.5521(13),β=115.119(3)o,V=1893.7(2)3,Z=4,Dc=1.893 g/cm3,μ=1.565 mm-1,F(000)=1072,C14H12AgClN4O4S3,Mr=539.78,T=293(2) K,S=1.067,the final R=0.0342 and wR=0.0870.The silver ion in the complex is in a trigonal coordin...     

Two Discrete Cu-Complexes Constructed from a Multidentate N-Containing Dinucleating Ligand

Two comparable discrete complexes [CuⅡ(CH3CN)2L2]·2(ClO4) 1 and [CuI2I2L2]·(DMF)2 2 were successfully synthesized by the reaction of CuⅡ and CuⅠ salts with a novel dinucleating ligand 2,5-bis(3-pyridinylmethylthio)-1,3,4-thiadiazole)(L),respectively.Complex 1 presents a single nuclear structure while 2 has a dimeric structure where two CuI ions are doubly bridged by halide ions in a μ2-fashion.Both discrete molecules were outspreaded into a one-dimensional supramolecular chain via aromatic interactions such as C-H…π and π…π interactions.     

线上教学的难题与解决方法*——大学化学慕课建设中的思考

利用中国大学 MOOC平台进行“大学化学”慕课的第二次录制。在本次课程的建设中,总结第一次录制时遇到的线上教学难题,提出“私人定制,以学为本,冲击高阶,求实创新”的新目标,开展分层递进等教学模式。实践表明,该模式可以满足不同基础学生的需求,大幅提高学习效率,克服线上教学学生基础差距大、教学效果反馈不及时等难题;同时兼具科普和思政教育效果。     

Synthesis,Crystal Structure and Fluorescence Properties of a 3D Framework Based on Hexanuclear Lanthanum 5-Nitroisophthalate Entities

The reaction of lanthanum(Ⅲ) nitrate and 5-nitroisophthalic acid in isopropanol/H2O under hydrothermal conditions leads to a 3D lanthanum-containing coordination polymer with the general chemical formula {[La6(Nip)9(H2O)4 ]·(H2O)4 }∞(1,Nip=5-nitroisophthalate).The single-crystal X-ray analyses show that this compound crystallizes in the orthorhombic system,space group Ima2 with a=9.7769(12),b=28.239(3),c=21.149(2),V=5839.1(11)3,Z=2,Mr=2859.61,Dc =1.626 g/cm 3,F(000)=2752.14040 reflections are collected,of which 5275 are unique (R int=0.0241).Final GOOF=1.083,R=0.0406 and wR=0.1182,R indices based on 5183 reflections with I>2σ(I)(refinement on F2),443 parameters,1 restraint.Lp and absorption corrections were applied,=2.242mm-1.Absolute structure parameter x=0.08(3).The crystal structure can be described as the butterfly-liked hexanuclear lanthanum entities {La6O6(CO2)8 } covalently linked to each other by nitroisophthalate ligands into an intricate three-dimensional structure.The fluorescence spectroscopy of compound 1 has been investigated.     

二维网格结构的新型配位聚合物[Zn(PDA)]n的合成、晶体结构及荧光性质

以2,6-吡啶二酸为配体, 与锌盐通过水热合成法得到具有二维网格结构的新型配位聚合物[Zn(PDA)]n(PDA=2,6-吡啶二羧酸根); 采用红外光谱、元素分析、热重分析及单晶X射线衍射等手段对[Zn(PDA)]n的晶体结构进行了表征. 并进一步研究了[Zn(PDA)]n的荧光性质.     

Synthesis, Crystal Structure and Magnetic Property of the Polymeric Ribbon： [Co（ip）（phen）]n

1 INTRODUCTION The design and synthesis of metal-organic coor- dination polymers are of current interest owing to their intriguing architectures and potential applica- tions, such as catalysis, fluorescence and magne- tism[1～4]. Many transition metal-organic polymers have been synthesized and exhibit interesting magneticproperties[5～9]. Among them, coordination polymers constructed by dicarboxylate ligands have attracted considerable attention due to their rich coordination modes and di…     

原子级分散Fe-N-C温和条件下选择性氧化催化特性

采用非溶液法制备了原子级分散的Fe-N-C催化剂, 并用于硫醚和二级醇的选择性氧化. 研究结果表明, 这种原子级分散的Fe-N-C催化剂可在温和条件下选择性地将硫醚转化为亚砜, 而不会产生过度氧化的砜. 该工艺具有反应条件温和、 反应速度快、 收率高等优点; 该催化剂对二级醇氧化制酮反应具有较高的催化活性, 产率较高. 作为一种非均相催化剂, Fe-N-C催化剂循环使用5次后活性未见显著下降; 在实验结果和参考文献的基础上还提出了一种可能的自由基反应机理.     

Hydrogen-bonded Three-Dimensional Networks Encapsulating One-dimensional Covalent Chains: [Cu(3-ampy)(H_2O)_4](SO_4)·(H_2O) (3-ampy = 3-Aminopyridine)

A three-dimensional complex [Cu(3-ampy)(H2O)4](SO4)·(H2O) (3-ampy = 3-amino- pyridine) has been synthesized. Crystallographic data: C5H16CuN2O9S, Mr = 343.80, triclinic, space group P1, a = 7.675(2), b = 8.225(3), c = 10.845(3) A, α = 86.996(4), β = 76.292(4), γ = 68.890(4)°, V = 620.0(3) A3, Z = 2, Dc = 1.841 g/cm3, F(000) = 354 and μ = 1.971 mm-1. The structure was refined to R = 0.0269 and wR = 0.0659 for 1838 observed reflections (I > 2σ(I)). The structure consists of [Cu(3-ampy)(H2O)4]2+ cations, SO42- anions and lattice water molecules. 3-Ampy acting as a bidentate bridging ligand generates a 1D covalent chain. A supramolecular 2D framework is formed through π-π stacking of pyridine rings. The lattice water molecules and SO42- anions are located between the adjacent 2D frameworks. The hydrogen bonding interactions from lattice water molecules and SO42- anions to coordinate water extend the 2D framework into a 3D network.     

Nitrogen-rich 6-（3,5-Dimethylpyrazol-1-yl）-3-（2,4,6-trinitroanilino）-1,2,4,5-tetrazin： Synthesis, Crystal Structure and Thermal Property

6-（3,5-Dimethylpyrazol-1-yl）-3-（2,4,6-trinitroanilino）-1,2,4,5-tetrazin （1） has been synthesized and characterized by ^1H NMR, MS, elemental analysis, infrared spectra and thermal analyses. The crystal structure was determined by X-ray diffraction method. 1 is crystallized in P21/c space group of monoclinic crystal system, and exhibits good physical properties, such as high densities （〉 1.55 g·cm^-3） and good thermal stabilities （Td〉220 ℃）. The intrermolecular hydrogen bonds construct the P- and M-helices from organic molecules and may contribute to the high melting points.