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111.
1 INTRODUCTION donor due to the presence of the protonated carboxyl group; (d) it can form short bridges via one car- Coordination polymers are of great interest due to boxylato end or long bridges via the benzene ring[7]. their physical properties and potential applications in We believe that coordination functionality of isoph- functional materials[1~3]. Aromatic polycarboxylic acids thalate can lead to interesting structures. In this com- such as 1,2,4,5-benzenetetracarboxylic acid[4],… 相似文献
112.
A Cu(Ⅱ) complex [Cu(L)1.5(OSO3)]·3H2O (1) [L=1,4-bis(imidazol-1-yl)benzene] was synthesized by reaction of ligand L with CuSO4·5H2O using solvothermal method and its structure was determined by X-ray crystal structure analysis. The structure indicates that the complex crystallizes in triclinic, space group P1 with a=0.948 8(2), b=1.078 5(2), c=1.108 4(2) nm, α=74.820(2), β=81.331(2), γ=72.638(2)°, V=1.041 5(3) nm3, Z=2, Dcalc=1.687 g·cm-3, F(000)=544, μ=1.205 cm-1, the final R=0.062 3 and wR=0.132 8. The Cu(Ⅱ) atom has distorted square-pyramidal environment with a N3O2 donor set. Each L ligand links two Cu(Ⅱ) atoms using its imidazole groups to form an infinite one-dimensional (1D) ladder-like chain, which further linked by SO42- to form a two-dimensional (2D) network structure. The 2D sheets are further connected by C-H…O hydrogen bonds to give a three-dimensional (3D) structure. CCDC: 650388. 相似文献
113.
114.
Five new thiophene imides having the structures C4H3SC(O)N(H)C(O)R (where R=Me, Et, Pr, t-Bu, 1-4) and C4H3SCH2C(O)N(H)C(O)CH35 have been prepared. Control over the orientation of the carbonyl groups was achieved by the introduction of a bulky group in the terminal position of the side chain, and molecular modeling calculations indicated that the energy difference between the ct and tt conformations is small. The acidity of 1-4 decreases from Me to t-Bu, and, although 1-4 will not undergo oxidative polymerization, the introduction of a single spacer CH2 group allows 5 to polymerize. 相似文献
115.
116.
在 THF中 ,通过三甲硅基环戊二烯基锂与四氯化锆反应合成了标题化合物 ,经元素分析 ,IR和 1 H NMR谱表征了其结构 ,并用 X-射线衍射测定了晶体结构 ,该晶体属于三斜晶系 ,空间群为 P1 ,晶体学参数 :a=0 .6787(6) ,b=1 .2 92 4 (2 ) ,c=1 .30 34(2 ) nm,α=67.83(1 ) ,β=82 .50 (3) ,γ=75.64 (3)°,V=1 .0 2 5nm3 ,Z=2 ,Dx=1 .41 5 g· cm-3 ,μ=8.989cm-1 ,F (0 0 0 ) =448,R=0 .0 32。质谱研究表明 ,化合物在质谱过程中发生二聚 C*p2 ZrClZr C*P2Cl(C*P=C5H4Si Me3 )。 相似文献
117.
4-Isopropoxalyl-1,5-diphenyl-2,3-dihydro-2,3-pyrroledione reacts with thiosemicarbazide to form (3aS*)(4R*)(6aR*)-4,6a-dihydroxy-4-isopropoxycarbonyl-1-thiocarbamoyl-3,5-diphenyl-1,3a,4,5,6,6a-hexahydropyrrolo[3,4-d]pyrazol-6-one. The molecular and crystal structure of the latter was studied by single crystal X-ray diffraction. 相似文献
118.
Rong‐Min Wang Nai‐Pu He Yu‐Feng He Yun‐Tao Xie Yun‐Pu Wang Eishun Tsuchida 《先进技术聚合物》2005,16(8):638-641
Water‐soluble low molecular weight chitosan of nanometer level and its copper complexes were prepared, and characterized by IR spectra, elemental analysis and gel permeation chromatography (GPC). The modes and mechanism of these copper complexes interaction with DNA were studied by a fluorescent probe method and electrophoresis analysis. It is suggested that there are electrostatic and intercalation modes of copper complexes interacting with DNA. At first, the cationic complex electrostaticly binds to the negatively charged phosphate backbone of DNA, and then a portion of the complex intercalates between the base pairs on the DNA duplex strand. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
119.
一水草酸铵(简称AOM)是一种优良的电光晶体 ̄[1]。文献 ̄[1,2]报道了该晶体的晶体结构,化学式为(NH_4)_2C_2O_2·H_2O,属正交晶系,P222空间群,晶胞参数a=0.8035nm,b=1。031nm,c=0.3801nm,z=2。本文拟报道AOM单晶生长,热化学分析,透过波段以及非线性光学性质的初步研究。 相似文献
120.
Jun Fan Wei‐Guang Zhang Min‐Yu Tan Yu Tang Wei‐Sheng Liu Ning Tang Kai‐Bei Yu 《中国化学》2004,22(6):508-511
The La(III) complex with a new amide‐type tripodal ligand,2,2′.2″‐nitrilotris{[(2′‐benzylaminofomyl)‐phenoxylethyl)amine (L), was synthesized and characterized by X‐ray crystallographic analysis. Crystal data: C48H55.50LaN7O18.75, Mr=1169.40, monoclinic. space group, P21/n, a= 1.0644(3) nm. b=2.3889(5) nm, c= 2.1917(5) nm, β=90.65°, V=5.573(2) nm3, Z=1, Dc=1.394 g°cm?3, R1=0.0487, wR [1>2s?(I)]=0.1266. The results reveal that each La(III) ion binds to 9 oxygen atoms, three of which belong to carbonyl groups from three tripodal ligands and six to three bidentate nitrate groups and a two‐dimensional sheet of 4.82 networks is assembled by metal‐ligand coordination interaction. L, a heptadentate compound, merely acts as a tridentate bridging spacer due to its steric hindrance and links the La(III) ions as three‐connected nodes. 相似文献