New approaches towards the synthesis and characterization of alkoxy substituted spirobifluorenes and spirosilabifluorenes for organic optoelectronics

Alkoxy substituted spirobifluorene derivatives namely 2,2′,7,7′-tetrabromo-3,6-bis(methoxy)-9,9′spirobifluorene (MSBF), 2,2′,7,7′-tetrabromo-3,6-bis(ethoxy)-9,9′spirobifluorene (ESBF), 2,2′,7,7′-tetrabromo-3,6-bis(butoxy)-9,9′spirobifluorene (BSBF), 2,2′,7,7′-tetrabromo-3,3′,6,6′-tetra(methoxy)-9,9′-spiro-9-silabifluorene (MSSiBF) and their key intermediates have been synthesised successfully. All compounds have been fully characterised by ¹H and ¹³C NMR, FTIR, UV-visible spectroscopy, MS spectrometry. TGA analysis revealed good thermal stability. The systematic investigation on the solubility, thermostability and photophysical property of synthesized compound showed that alkoxy substituted spirobifluorene were unique in rigidity and have wide range of applications in molecular electronics and can be used as building units for optoelectronics material.     

Silica-gel-supported Ce(SO4)2·4H2O-mediated cyclization of 2′-amino and 2′-hydroxychalcones under solvent-free conditions

A simple, efficient, and environmentally friendly approach for the synthesis of flavones, aza-flavones, and aza-flavanones from corresponding 2′-hydroxy or 2′-aminochalcones has been developed. The reactions are successfully conducted in presence of silica-gel-supported Ce(SO₄)₂·4H₂O under solvent-free conditions.     

In situ Alkylation of 4,4′‐Vinylenedipyridine for Inorganic‐Organic Iodides/Iodidomercurates

Solvothermal reactions of HgI₂, 4,4′‐vinylenedipyridine, and HI in alcoholic solution (methanol, ethanol, or pentanol) gave rise to a family of organic‐inorganic hybrid complexes, formulated as [C₁₄H₁₆N₂][I₄]^2– ( 1 ), [C₁₆H₂₀N₂][HgI₄] ( 2 ), and [C₂₂H₃₂N₂][HgI₄]₄ ( 3 ). Single‐crystal X‐ray diffraction reveals that all three compounds are discrete structures, including the inorganic anion [I₄]^2– or [HgI₄]^2– and an organic cation, where the resulting organic cations were generated in situ alkylation reactions of 4,4′‐vinylenedipyridine with alcohols, with cleavage of the alcoholic C–O bond followed by a one‐step in situ N‐alkylation reaction of 4,4′‐vinylenedipyridine in acidic HI solution. X‐ray powder diffraction (XRD), ¹H NMR and ¹³C NMR, energy‐dispersive X‐ray (EDS), IR, as well as UV/Vis/NIR spectroscopy, elemental analysis, and thermogravimetric analysis (TGA) were used to characterize the complexes.     

Three isotypic polymeric complexes with rare earth cations,but‐2‐enoate anions and 4,4′‐(ethane‐1,2‐diyl)dipyridine and 4,4′‐(ethene‐1,2‐diyl)dipyridine bridging ligands

Three isotypic rare earth complexes, catena‐poly[[aquabis(but‐2‐enoato‐κ²O,O′)yttrium(III)]‐bis(μ‐but‐2‐enoato)‐κ³O,O′:O;κ³O:O,O′‐[aquabis(but‐2‐enoato‐κ²O,O′)yttrium(III)]‐μ‐4,4′‐(ethane‐1,2‐diyl)dipyridine‐κ²N:N′], [Y₂(C₄H₅O₂)₆(C₁₂H₁₂N₂)(H₂O)₂], the gadolinium(III) analogue, [Gd₂(C₄H₅O₂)₆(C₁₂H₁₂N₂)(H₂O)₂], and the gadolinium(III) analogue with a 4,4′‐(ethene‐1,2‐diyl)dipyridine bridging ligand, [Gd₂(C₄H₅O₂)₆(C₁₂H₁₀N₂)(H₂O)₂], are one‐dimensional coordination polymers made up of centrosymmetric dinuclear [M(but‐2‐enoato)₃(H₂O)]₂ units (M = rare earth), further bridged by centrosymmetric 4,4′‐(ethane‐1,2‐diyl)dipyridine or 4,4′‐(ethene‐1,2‐diyl)dipyridine spacers into sets of chains parallel to the [20] direction. There are intra‐chain and inter‐chain hydrogen bonds in the structures, the former providing cohesion of the linear arrays and the latter promoting the formation of broad planes parallel to (010).     

A new proline-containing flavonol glycoside from Caragana leucophloea Pojark

One new proline-containing flavonol glycoside, namely kaempferol-3-O-methyl-7-O-β-d-glucopyranosyl-8-(1-methyleneproline)-4′-O-β-d-glucopyranoside (1), together with 15 known flavonoids, 3-O-methylkaempferol (2), 3-O-methylquercetin (3), quercetin (4), kaempferol (5), apigenin (6), rhamnazin (7), astragalin (8), alquds (9), quercitrin (10), rutin (11), isoquercitrin (12), apigetrin (13), myricitrin (14), hesperidin (15) and calycosin-7-O-β-d-glucopyranoside (16) were isolated from the aerial parts of Caragana leucophloea Pojark. (Leguminosae). Their structures were determined on the basis of spectroscopic analyses and by comparison with literature data. Compounds 2–4 revealed a strong antimicrobial activity with minimum inhibitory concentration values of 12.5–150 μg/mL and median inhibitory concentration (IC₅₀) values of 7.42–76.61 μg/mL. Compounds 3, 4, 6–8, 10–12 and 14 showed strong antioxidant activity. Compounds 2–7 exhibited moderate antinematodal activity on Caenorhabditis elegans with IC₅₀ values of 40.51–68.05 μg/mL.     

快速显色法定性检测氨纶纺织品中4,4’-二氨基二苯甲烷

建立显色法测定氨纶纺织品中4,4’-二氨基二苯甲烷的方法。样品经二氯甲烷提取后,利用芳香胺重氮化产物与盐酸萘乙二胺发生偶合反应生成具有特征颜色的偶氮染料这一显色原理进行测定。方法检出限为5.0mg/kg。该方法显色灵敏,操作简便,快速,无需色谱仪器等大型设备。该方法可用于排除纺织品中含有4,4’-二氨基二苯甲烷。     

Structural diversity of a series of urea-based coordination complexes: from water tapes,water-sulfate chains,to supramolecular structures

[Hg₂(L₁)₂I₄] (1), [Cd₂(L₁)₂I₄] (2), {[Cd(L₁)₂(SO₄)(H₂O)]·4H₂O}_n (3), {[Zn₂(L₂)₂(Cl)₄]·0.5H₂O} (4), {[Cu₂(L₂)₂(SO₄)₂(H₂O)₄]·2.5H₂O} (5), and {[Cd(L₂)₂(SO₄)(H₂O)]·3H₂O}_n (6), based on N–(3–picolyl)–N′–(3–pyridyl)urea (L₁) or N–(4–picolyl)–N′–(3–pyridyl)urea (L₂), have been synthesized and characterized by elemental analyses, IR spectra, single-crystal and powder X-ray diffraction, and thermogravimetric analyses. Complexes 1 and 2 are isomorphous and feature similar rectangular metal organic loops, which were further extended into 2-D supramolecular structures through hydrogen bonds. Complex 3 possesses a 2-D sql sheet, and the channels between the neighboring sheets are filled with lattice water molecules, which formed a 1-D water tape. Complex 4 also exhibits a rectangular metal organic loop and a 3-D supramolecular structure with the help of hydrogen bonding interactions. Complex 5 also possesses a metal organic loop, and the water molecules interacted with sulfates, constructing a 1-D water–sulfate tube. Complex 6 features a 1-D loop polymeric chain. Moreover, the solid state luminescences of 1–4 and 6 have been investigated.     

Revealing the structural chemistry of the group 12 halide coordination compounds with 2,2′-bipyridine and 1,10-phenanthroline

The coordination compounds of group 12 halides with 2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen), 2[CdF₂(bpy)₂]·7H₂O (1), [ZnI(bpy)₂]⁺·I₃^? (2), [CdI₂(bpy)₂] (3), [Cd(SiF₆)H₂O(phen)₂]·[Cd(H₂O)₂(phen)₂]²⁺·F^–·0.5(SiF₆)^2–·9H₂O (4), [Hg(phen)₃]²⁺·(SiF₆)^2–·5H₂O (5), [ZnBr₂(phen)₂] (6), 6[Zn(phen)₃]²⁺·12Br^–·26H₂O (7) and [ZnI(phen)₂]⁺·I^– (8), have been synthesized and characterized by X-ray crystallography, IR spectroscopy, elemental and thermal analysis. Structural investigations revealed that metal?:?ligand stoichiometry in the inner coordination sphere is 1?:?2 or 1?:?3. A diversity of intra- and intermolecular interactions exists in structures of 1–8, including the rare halogen?halogen and halogen?π interactions. The thermal and spectroscopic properties were correlated with the molecular structures of 1–8. Structural review of all currently known coordination compounds of group 12 halides with bpy and phen is presented.     

Syntheses and characterization of two new compounds based on versatile 1,2,3,5-benzenetetracarboxylic acid and 2,2′-bibenzimidazole

Two coordination complexes based on H₄btec and H₂bibzim (H₄btec = 1,2,3,5-benzenetetracarboxylic acid, H₂bibzim = 2,2′-bibenzimidazole), [Ni(H₂bibzim)₃]₂(btec) (1) and [Zn(H₂bibzim)(btec)_0.5]_n (2), have been synthesized by hydrothermal methods and characterized by single-crystal X-ray diffraction. Complex 1 is composed of [Ni(H₂bibzim)₃]²⁺ with free btec^4? as counter anion. In 2, the btec^4? ligands bridge the Zn(II) ions into a 1-D chain with H₂bibzim as auxiliary chelating ligands. Interesting supramolecular structures were demonstrated due to the existence of hydrogen bonding as well as π?π interactions in the two different complexes. The H₂bibzim ligands act as a 2-connected spacer in both complexes. However, in 1, the [Ni(H₂bibzim)₃]²⁺ cations act as 3-connected nodes, hydrogen bonded with the 6-connected btec^4? ligands into a 3-D framework with (3,6)-connected topology Schläfli symbol as (4.6.8)(4².6)(4³.6⁴.8⁷.10). As for 2, Zn serves as a 3-connected node with btec^4? as a 6-connected node, leading to a 2D (3,6)-connected hydrogen bonding kgd topology sheet with Schläfli symbol of (4³)²(4⁶.6⁶.8³). Thermal stabilities and photoluminescent properties of 1 and 2 were also studied.     

线性流量阀内筒孔形状设计问题研究

对于双筒式线性流量阀,内筒孔形状设计是关系到线性流量阀的过流面积能否"线性变化"的核心问题.从工程实际应用出发,对线性流量阀的内筒孔进行了分段地形状设计.经设计的内筒设计能够使线性流量阀的线性控制区达到90%以上,"过流面积"也完全能够达到"最大范围".设计的内筒孔主体形状为矩形和简单曲线组成,易于加工制造.