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641.
Yuttawat Hashmi Assoc. Prof. Tienthong Thongpanchang 《European journal of organic chemistry》2023,26(4):e202201373
Novel benzo[1,2-b:4,3-b′]dinaphthofuran (oxa[7]helicene) with various substituents in the central ring were designed and successfully synthesized based on the late stage central ring formation strategy from naphthofuranoneby using an efficient McMurry coupling or Friedel-Crafts acylation. The photochemical properties of helicenes were evaluated by UV-Visible absorption spectroscopy and fluorescence spectroscopy, while electrochemical behaviour including their energy profile were investigated by cyclic voltammetry and DFT calculations. According to the computational study, substituents on the central ring could influence both electron delocalization and MO distribution of oxa[7]helicenes resulting in the change in charge transporting ability. In comparison to the parent carbo[7]helicene, the furan unit in conjunction with substituents on helical system caused the bathochromic shift with different absorption pattern and exhibited higher fluorescence quantum yield (ϕf up to 0.63). These new materials showed promising characteristics in optoelectronic application. 相似文献
642.
YU Ming-Ming KOU Hui-Zhong ZHAO Chong-Chao ZHENG Lei CUI Ai-Li 《结构化学》2008,27(5):610-615
Two complexes CuLCl(H2O) 1 and Ni(L)2 2 (HL = 2-carboxy-1,10-phenanthroline) have been synthesized and characterized by single-crystal X-ray crystallography. The structure of 1 has a monoclinic space group P21/n with a = 7.985(2), b = 16.067(3), c = 9.694(2) A, β = 98.189(30)°, V= 1231.0(4) A^3, Z = 4, Dc = 1.836 g/cm^3,μ =1.998 mm^-1, F(000) = 684, the final R = 0.0301 and wR = 0.0810. The structure of 2 (C26H14N4NiO10) adopts an orthorhombic system, space group Pbea with a = 9.410(2), b = 23.2410(5), c = 23.8680(5) A, V = 5219.9(18) A^3, Z = 8, Mr = 601.12, Dc = 1,530 g/cm^3,μ = 0.809 mm^-1, F(000) = 2448, the final R = 0.0448 and wR = 0.1427. The Cu center of complex 1 exhibits a square pyramidal coordination environment with one oxygen and two nitrogen atoms from deprotonated 2-carboxy-1,10-phenanthroline, one oxygen atom from water and one chloride ion. The Ni center of complex 2 assumes a distorted octahedral coordination geometry consisting of two oxygen atoms and four nitrogen atoms of two deprotonated 2-carboxy-1,10-phenanthroline molecules. Supramolecular assembly has been found via noncovalent bonds, such as hydrogen bonds and π-π stacking interactions. 相似文献
643.
644.
合成了新配合物[Cu(phen)2Cl].ClO4.H2O(phen=o-phenanthroline),并用IR和X射线单晶衍射法对其结构进行了表征.晶体结构解析表明,标题配合物属单斜晶系,空间群为P2(1)/n,晶胞参数a=1.18086(8)nm,b=1.52855(10)nm,c=1.29572(9)nm,α=90°,β=93.1770(10)°,γ=90.000°,V=2.3352(3)nm3,Z=4,Dc=1.641Mg/m3,Mr=576.86,μ=1.210mm-1,F(000)=1172,偏差因子R1=0.0481,wR2=0.1424.在配合物[Cu(phen)2Cl]·ClO4.H2O中,Cu(Ⅱ)离子处于四个N原子和一个Cl-离子构成的三角双锥几何构型中.分子间利用氢键作用,π-π堆积作用形成二维层状结构.层与层间通过弱氢键作用形成三维空间结构. 相似文献
645.
The vector correlations between products and reagents for the reactions Ne+H + 2 , Ne+D + 2 , and Ne+T + 2 are calculated by means of the quasi-classical trajectory method on a new potential energy surface constructed by Lü et al. [J. Chem. Phys. 2010 132, 014303]. The polarization-dependent differential cross-sections (2π/σ)(dσ 00 /dω t ), (2π/σ)(dσ 20 /dω t ), (2π/σ)(dσ 22+ /dω t ), and (2π/σ)(dσ 21 /dω t ), and the distributions of P (θ r ), P (φ r ), and P (θ r ,φ r ) are calculated. The isotopic effect, which is associated with the difference in mass factor among the three reactions, is revealed. 相似文献
646.
利用甜菜碱衍生物1,5-二(4-羧基吡啶基)-N-甲基二乙胺(L)合成了两种镉(Ⅱ)的配位化合物[Cd2Cl4(H2O)2L2].2H2O和[Cd2(SCN)4(μ-H2O)L2]。用X-射线单晶衍射仪测定了配合物的单晶结构,并对它们进行了元素分析、红外光谱、1H NMR、热重等表征。结构分析表明,前者具有三十六元大环框架,而后者为双环结构。由于缺乏分子之间的强烈相互作用,弱相互作用决定了这两种化合物在晶格中的堆积模式:前者由相邻分子间的π-π和C-H…π相互作用而堆积形成二维砖墙的结构;后者由配位的SCN-阴离子通过S…S弱相互作用联接成一维链状结构。 相似文献
647.
《Journal of Coordination Chemistry》2012,65(11):1249-1257
Reaction of freshly-prepared CoCO3, phenanthroline monohydrate and adipic acid (H2L) in CH3OH/H2O produced a mixture of [Co(phen)(H2O)4]L·0.5H2O (1) and [CO2(phen)2(H2O)2L2] (2). Complex 1 crystallizes in the orthorhombic space group Pbcn with cell dimensions a = 23.380(2), b = 12.347(1), c = 12.821(1) Å, and D calc = 1.390 g/cm3 for Z = 8, and complex 2 in the triclinic space group P1; with cell dimensions a = 8.203(1), b = 9.809(1), c = 11.827(1) Å, α = 70.34(1), β = 74.81(1), γ = 71.54(1)° and D calc = 1.592 g/cm3 for Z = 1. Complex 1 consists of [Co(phen)(H2O)4]2+ complex cations, adipate anions and crystal H2O molecules. The Co atoms are each octahedrally coordinated by one chelating phen ligand and four water molecules with d(Co-O) = 2.041-2.097 Å and d(Co-N) = 2.144, 2.160 Å. Through hydrogen bonds, the [Co(phen)(H2O)4]2+ complex cations and adipate anions are interconnected into 2D layers, whose assembly could be ascribed to weak π-π stacking interactions between interdigitating phen ligands. Complex 2 is composed of centrosymmetric dinuclear [Co2(phen)2(H2O)2L2) molecules, in which the Co atoms are each coordinated by two N atoms of one chelating phen ligand and four O atoms of one H2O molecule and two adipato ligands to form distorted octahedra with d(Co-O) = 2.027-2.248 Å and d(Co-N) = 2.112, 2.162 Å. The centrosymmetric molecules are assembled via intermolecular hydrogen bonds and π-π interactions into 2D layers. 相似文献
648.
《Journal of Coordination Chemistry》2012,65(3):257-264
A binuclear terbium(III) complex of N-(2-pyridinyl)ketoacetamide (HL) was synthesized and its crystal structure determined. Each terbium(III) binds to one N,O-bidentate HL, one O,O-bidentate L and two N,μ-O,O-tridentate bridging L ligands; the coordination polyhedron is a distorted square antiprism. The pyridine N and keto O atoms of the binucleating ligand are coordinated to each Tb with the amide O acting as a bridging atom. The adjacent [Tb2(HL)2L4]2+ units are bridged by double C(R)NH…ONO2…HN(R)C hydrogen bonds to form an infinite 1-D chain, and a 2-D layer structure results from a rare near face-to-face π,π-stacking interaction between the pyridine rings of the adjacent chains. The crystal structure analysis reveals that the ligands completely shield the Ln(III) ions. Excited by the absorption band at 370?nm, the Tb(III) complex displays characteristic metal-centered fluorescence while the ligand fluorescence is completely quenched, showing that efficient ligand-to-metal energy transfer (antenna effect) occurs. 相似文献
649.
《Journal of Coordination Chemistry》2012,65(19):2067-2074
Two isomorphous one-dimensional chain complexes Co(NCS)2(Him)2 (1) and Mn(NCS)2(Him)2 (2) (Him?=?imidazole) have been prepared and characterized structurally. Both 1 and 2 crystallize in the monoclinic system, space group P21/n, and the structures consist of one-dimensional polymeric chains in which metal ions are bridged by two thiocyanate groups bonding in end-to-end fashion. Both 1 and 2 exhibit two-dimensional sheet structures with N–H?···?S hydrogen bonds and three-dimensional supramolecular network structure with π?···?π stacking interactions. IR spectra indicate the presence of bridging thiocyanate groups in both 1 and 2, confirmed by their structures. The variable temperature magnetic susceptibility, measured in the 2–300?K range, indicates weak antiferromagnetic exchange interactions in complex 2. 相似文献
650.
《Journal of Coordination Chemistry》2012,65(17):3102-3109
Two new linear trinuclear complexes, [Co(NiL1)2(SCN)2] (1) and [Co(NiL2)2(H2O)2](ClO4)2?·?2C2H5OH (2), have been prepared by using Co(ClO4)2?·?6H2O and two macrocyclic complex ligands NiL1 and NiL2. L1 and L2 are the doubly deprotonated forms of dimethyl 5,6,7,8,15,16-hexahydro-6,7-dioxodibenzo[1,4,8,11]tetraazabicyclo[12.4.015,16]13,18-dicarboxylate and dimethyl 5,6,7,8,15,16-hexahydro-15-methyl-6,7-dioxodibenzo[1,4,8,11]tetraazacyclotetradecine-13,18-dicarboxylate, respectively. X-ray single crystal analyses reveal the coordination geometries around Ni(II) in both 1 and 2 are identical and slightly distorted square planar with N4 donors; all Ni–N bonds in the two complexes are very short. The Co(II) ions are at the centers of the trinuclear complexes and have distorted octahedral coordination geometries of O4N2 donors in 1 and an O6 in 2. π?···?π interactions involving aromatic and non-aromatic π-systems join the trinuclear entities to form 2-D layers in the crystals of 1 and 2. 相似文献