有机锡4-(4-吡啶基甲基硫代)苯甲酸酯的合成、结构与生物活性研究

通过4-（4-吡啶基甲基硫代）苯甲酸与三苯基氧化锡以及三环己基氢氧化锡反应,合成了三苯基锡4-（4-吡啶基甲基硫代）苯甲酸酯（1）及三环己基锡4-（4-吡啶基甲基硫代）苯甲酸酯（2）。它们的结构通过红外,核磁以及X-射线单晶衍射分析得到确证。化合物1表现为一维链状结构,而化合物2通过分子间的O-H…O和O-H…N氢键形成二维网状结构。生物活性测试表明,这2个化合物具有较高的抗肿瘤活性。     

Synthesis of dendritic carbohydrate end‐functional polymers via RAFT: Versatile multi‐functional precursors for bioconjugations

Well‐defined pyridyl disulfide (PDS) end‐functionalized polymer‐dendritic carbohydrate scaffolds are reported as novel precursors for the attachment of biomolecules. This synthetic approach combines reversible addition fragmentation chain transfer (RAFT) polymerization and “click” reactions. Poly(N‐(2‐hydroxypropyl) methacrylamide) (PHPMA) with 2‐mercaptothiozalidine end‐groups was prepared by RAFT polymerization yielding molecular weights of M_n = 4300 and 9900, both with a polydispersity of less than 1.2. These polymers were then attached to dendritic mannose scaffolds preconstructed via consecutive “click” reactions. Finally, the ω‐dithiobenzoate RAFT end‐group of PHPMA was modified to yield PDS functionality, by aminolysis in the presence of 2,2′‐dithiodipyridine. This PDS end‐functionalized PHPMA‐dendritic carbohydrate scaffold is a versatile precursor for bioconjugations, as the synthetic procedure can easily accommodate a range of sugar functionalities. In addition, the PDS groups can be used to react with any thiol present in a biomolecule (e.g., cysteine residue in proteins, or ? SH terminal nucleotides). To demonstrate the utility of these scaffolds we describe their bioconjugation to short interfering RNA. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4302–4313, 2009     

Proton‐controlled nitroxide mediated radical polymerization of styrene

The pyridyl alkoxyamine, which is composed of the 1‐phenylethyl radical and a pyridyl nitroxide fragments, displays protonation‐controlled C? ON bond homolysis. Its dissociation rate constant k_d value is approximately halved at 100 °C in tert‐butyl benzene when it is protonated by one equivalent of trifluoroacetic acid. Moreover, the bulk polymerization of styrene at 125 °C is performed with a good control over the molecular weight and the dispersity when initiated with this alkoxyamine under its basic and acidic forms but the protonation has induced a strong decreased polymerization rate. In contrast, in the case of n‐butyl acrylate, the control over the polymerization is lost for the protonated pyridyl alkoxyamine because the pyridyl nitroxide is less thermally stable under its acidic form. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Synthesis,characterization and crystal structure of a novel 2D Ni(II) complex with malate

An exploration of the nickel‐ malate‐bpa system under hydrothermal conditions, has led to the isolation of a novel framework {[Ni(Hmal)(bpa)]·2.5H₂O}_n ( 1 ) (Hmal = malate dianion, bpa = 1,2‐bi(4‐pyridyl)ethane). Single‐crystal X‐ray analyses reveal that it crystallizes in the orthorhombic space group Fdd2. a = 21.9944(13) Å, b =33.3369(19) Å, c = 10.3969(5) Å, β = 90°. The Ni^II ions are linked into an extended helical chain via Hmal molecules. Further these chains are united together through the bridging bpa to form a 2D grid layer, which exhibits a typical (6,3) topological network. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

联吡啶四唑铜(II)配合物的原位合成、结构及性质

采用水热合成法,通过配体5,5'-二氰基-3,3'-联吡啶和叠氮化钠在路易斯酸CuSO₄的作用下,得到了一种新型的金属有机铜四唑配合物。 X射线单晶衍射结构表明,该化合物属于四方晶系,P4/ncc空间群。它是由吡啶环中的N原子连接形成的无限延展的二维网状结构;硫酸根阴离子位于中心金属周围,且高度无序的硫酸根离子很有可能在低温下变成有序,从而引起结构相变。该化合物的堆积图形状类似一个蝴蝶发卡。 其高含氮结构可作为潜在的高含能材料。     

Assembly,Structures, and Properties of a Series of Metal‐Organic Coordination Polymers Derived from a Semi‐rigid Bis‐pyridyl‐bis‐amide Ligand

Four metal‐organic coordination polymers [Cd(4‐bpcb)_1.5Cl₂(H₂O)] ( 1 ), [Cd(4‐bpcb)_0.5(mip)(H₂O)₂] · 3H₂O ( 2 ), [Co(4‐bpcb)(oba)(H₂O)₂] ( 3 ), and [Ni(4‐bpcb)(oba)(H₂O)₂] ( 4 ) [4‐bpcb = N,N′‐bis(4‐pyridinecarboxamide)‐1, 4‐benzene, H₂mip = 5‐methylisophthalic acid, and H₂oba = 4, 4′‐oxybis(benzoic acid)] were synthesized under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction, elemental analyses, IR spectroscopy, powder X‐ray diffraction, and TG analysis. In complex 1 , two Cl^– anions serve as bridges to connect two Cd‐(μ₁‐4‐bpcb) subunits forming a dinuclear unit, which are further linked by μ₂‐bridging 4‐bpcb to generate 1D zigzag chain. Complex 2 shows a 2D 6³ network constructed by [Cd‐mip]_n zigzag chains and μ₂‐bridging 4‐bpcb ligands. Complexes 3 and 4 are isostructural 2D (4, 4) grid networks derived from [M‐oba]_n (M = Co, Ni) zigzag chains and [M‐(4‐bpcb)]_n linear chains. The 1D chains for 1 and the 2D networks for 2 – 4 are finally extended into 3D supramolecular architectures by hydrogen bonding interactions. The roles of dicarboxylates and central metal ions on the assembly and structures of the target compounds were discussed. Moreover, the thermal stabilities, photoluminescent properties, and photocatalytic activities of complexes 1 – 4 and the electrochemical properties of complexes 3 and 4 were investigated.     

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.     

Iridium(I) pyridyl azolate complexes with saturated red metal-to-ligand charge transfer phosphorescence; fundamental and potential applications in organic light-emitting diodes

Preparation of a new series of neutral metal complexes [(cod)Ir(fppz)] (1), [(cod)Ir(bppz)] (2), [(cod)Ir(fptz)] (3) and [(cod)Ir(bptz)] (4), bearing one cod ligand and a pyridyl azolate chelate are reported. A single-crystal X-ray diffraction study of 3 reveals the expected distorted square-planar geometry. The lowest absorption band consists of IrI atom increased triplet dpi-->pi* transitions (3MLCT), the assignment of which is firmly supported by the theoretical approaches. Complexes 1-4 exhibit weak phosphorescence in degassed solution at room temperature, whereas much more intense, solid-state phosphorescence appears in the range 622-649 nm. The pure MLCT emission was used as a prototypical model to address its remarkable spectral differences from the IrIII isoquinoline pyrrolide complex (5), which has mainly 3pipi phosphorescence. Complex 3 was used as a dopant to fabricate red-emitting phosphorescent organic light-emitting diodes (OLEDs). For the 7 % doped device, a maximum brightness of 3010 cd m-2 was achieved at an applied voltage of 15 V and with CIE coordinates of (0.56, 0.33), demonstrating for the first time the potential of neutral IrI complexes in OLED applications.     

A Flat Model Approach to Tethered Bis(imino)pyridyl Iron Ethylene Polymerization Catalysts

A surface science model for a silica supported bis(imino)pyridyl iron complexes is applied to reveal the surface chemistry of these heterogeneous polymerization catalysts. The polymerization activity of these models and the molecular weight distribution of the resulting polymer are comparable to similar catalysts supported on amorphous silica. The catalyst deactivates partially during the first hour of ethylene polymerization. Based on photoelectron spectroscopy (XPS) we attribute this deactivation to iron extrusion by the aluminium alkyl activator.