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1.
在自然界中,α-羟基羧酸广泛的存在于动植物体内,在羧酸循环、碳水化合物代谢和氨基酸的合成中起到重要的作用。Tapscott等详细总结了有关羟基羧酸及其金属配合物的合成化学[1]。芴的9位上2个氢原子被羟基和羧基取代可生成9-羟基-芴-9-羧酸(简称芴酸),它是α-羟基乙酸的衍生物,是一种具有生理活性的植物生长整形素,它能够延缓植株生长,影响植株根的向地性和茎的向光性[2]。由于芴酸含有羟基和羧基两种不同的氧配位原子,使其又可以作为一种潜在的构筑配合物的组织基元。目前有关芴酸与金属离子的合成与结构化学研究相对较少,仅见铜、镉的单… 相似文献
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0IntroductionThe solid-state chemistry of manganese!car-boxylate coordination polymers has received growingattention over the past few years,owing to their fasci-nating network topologies and potential application inthe field of molecular magnetism and bi… 相似文献
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A novel coordination polymer of [Sr2(4-CPOA)2(H2O)5]n (where 4-CPOA2- is 4-carboxylphenoxyacetate) has been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The title complex belongs to monoclinic system with space group C2/c, a=2.563 9(5) nm, b=1.162 7(2) nm, c=0.742 96(15) nm, β=99.64(3)°. V=2.183 5(7) nm3, Z=4, Mr=653.60, Dc=1.988 g·cm-3, R=0.027 8, wR=0.058 1. The strontium atom has a bicapped triangular prismatic coordination geometry, involving four oxoacetate oxygen atoms, one ether oxygen atom from different 4-CPOA2- ligands and three water molecules. The strontium(Ⅱ) ions are linked by 4-CPOA2- ligands and water molecules to form a 3D network structure. CCDC: 223313. 相似文献
4.
A novel 1-D Cd(Ⅱ) coordination polymer, [Cd(p-BDOA)·2H2O]n(I) ( p-BDOA2-=benzene-1,4-dioxyacetate dianion) has been synthesized and characterized by elemental analysis, IR, PL, TG and X-ray single crystal diffraction. The Crystal crystallizes in monoclinic system, the space group is C2/c, with the crystal cell parameters a=1.175 1(1) nm, b=0.551 0(1) nm, c=1.827 7(2) nm, β=96.14(2)°, and V=1.176 6(3) nm3,, Mr=372.60, R=0.045 9, wR=0.127 9. The Cd(Ⅱ) ion has a trigonal prism coordination configuration that defined by four carboxyl O atoms from two different p-BDOA2- ligands and two water molecules. Adjacent Cd(Ⅱ) ions are linked by carboxylate groups with the bidentate coordination mode, giving rise to a chain structure with the adjacent Cd…Cd distance of 1.526 3(5) nm. Furthermore, such chains are linked by hydrogen bonds to form supramolecular network. The results of PL and TG show that the complex exhibits intense fluorescent emissions and its chain skeleton is thermally stable up to 419 K. CCDC: 220443. 相似文献
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本文合成了1个新的一维配位聚合物[Cu(apy)(sal)2]n(apy=2-氨基嘧啶,sal=水杨醛),并对其进行了元素分析、红外、热重、紫外、核磁、粉末XRD及单晶X-射线衍射表征。该聚合物为三斜晶系,空间群P1,a=0.726 87(15)nm,b=0.914 41(18)nm,c=1.382 0(3)nm,α=108.74(3)°,β=94.13(3)°,γ=96.64(3)°,V=0.858 2(3)nm 3,Z=2,R=0.087 8。Cu(Ⅱ)离子分别与来自2个不同水杨醛配体中的4个氧原子以及2个不同2-氨基嘧啶配体中的2个氮原子配位,形成了1个八面体配位构型。2-氨基嘧啶配体桥联相邻的Cu(Ⅱ)离子形成了沿bc平面的一维折叠链状结构,其相邻Cu(Ⅱ)离子之间的距离为0.6954 nm。此外,相邻的链中水杨醛的芳环之间存在着π-π堆积作用,该芳环堆积作用使得配合物构筑成二维超分子层状结构。 相似文献
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A novel one-dimensional coordination polymer, {[Cd(PAc)2(4,4-bipy)(H2O)]·4H2O}n (HPAc=phenyl acetic acid, 4,4′-bipy=4,4′-bipyridine) was synthesized and characterized by element analysis, IR, TG and X-ray single diffraction crystal structure determination. It crystallizes in the monoclinic space group C2/c with a=2.088 5(4) nm, b=0.839 05(17) nm, c=1.683 5(3) nm, β=105.45(3)° and V=2.843 5(10) nm3, Z=4, Mr=628.94, F(000)=1 288, μ=0.820 mm-1, R=0.019 9, wR=0.056 5. Each cadmium(Ⅱ) atom is seven-coordinated by four oxygen atoms from two different phenyl acetate groups and two nitrogen atoms from two 4,4′-pyridine ligands and one water molecule, forming a distorted pentagonal bipyramid coordination geometry. Adjacent cadmium(Ⅱ) atoms are bridged by 4,4′-pyridine ligand, constructing a infinite chain along the diagonal direction of ac plane. The Cd…Cd separation within the polymer is 1.164 6(4) nm. The three-dimensional supramolecular structures of the title complexes are constructed by hydrogen bonding interactions and π-π stacking interactions between the benzene rings of HPAc and 4,4′-bipy. CCDC: 616697. 相似文献
10.
A two-dimensional coordination polymer, [Cu(PAc)2(μ-3-PyOH)2]n(HPAc=phenyl acetic acid, 3-PyOH=3-hydroxypyridine) was synthesized and characterized by the element analysis, IR, TG and X-ray diffraction single crystal structure determination. The title complex crystallizes in the monoclinic system with space group P21/c, a=1.228 7(3) nm, b=0.967 05(19) nm, c=1.076 4(2) nm, β=109.93(3)° and V=1.202 4(5) nm3, Z=2, Mr=524.01, F(000)=542, μ=0.953 mm-1, R=0.030 9, wR=0.080 7. Each copper(Ⅱ) ion displays an elongated octahedron with two nitrogen atoms from two different 3-PyOH ligands and two oxygen atoms from two different terminal phenyl acetate groups occupying the basal positions and two oxygen atoms of two different 3-PyOH ligands from the neighbouring molecules occupying the axial positions. Each four identical mononuclear Cu(Ⅱ) unit in the two-dimensional layer is joined by four 3-PyOH ligands, related by inversion centers with a Cu…Cu separation of 0.723 5(10) nm across the 3-PyOH-N,O bridge in bc plane. CCDC: 664483. 相似文献