排序方式: 共有114条查询结果,搜索用时 62 毫秒
51.
Arno F. Stassen Eugenia Martínez Ferrero Carlos Giménez-Saiz Eugenio Coronado Jaap G. Haasnoot Jan Reedijk 《Monatshefte für Chemie / Chemical Monthly》2003,134(2):255-264
Summary. The synthesis, crystal structure and physical properties of the complex obtained from the reaction between the polyoxometalate
anion [PMo12O40]3−, copper(II) and the ligand 1-(2-chloroethyl)tetrazole (teec) are described. This compound has been synthesized as a model for designing materials containing both magnetic polyoxometalate
anions and iron(II) spin-crossover cations.
The compound, with formula [Cu(teec)5]2[Cu(teec)6][PMo12O40]2·2H2O, consists of alternating layers of polyoxometalates and cationic complexes. Both, five and six coordinated Cu(II) ions are
present, each positioned in different layers. Despite these layers having a similar width, the layer of pentacoordinated Cu(II)
ions contains twice as many cationic complexes as the layer of hexacoordinated Cu(II) ions. This unusual coexistence of complexes
with different coordination number is most likely caused by the steric hindrance induced by the bulky polyoxometalates in
the layer of pentacoordinated Cu(II) which prevents the presence of a sixth teec ligand.
Corresponding author. E-mail: haasnoot@chem.leidenuniv.nl
Received June 5, 2002; accepted June 12, 2002 相似文献
52.
Tienan Jin 《Tetrahedron letters》2004,45(51):9435-9437
1-Substituted tetrazoles were synthesized via the [3+2] cycloaddition between isocyanides and trimethylsilyl azide in the presence of an acid catalyst and MeOH. Various 1-substituted tetrazoles were obtained in good to high yields. The reaction probably proceeds through the in situ formation of hydrazoic acid, followed by a successive [3+2] cycloaddition with the isocyanide activated by an acid. 相似文献
53.
54.
本文通过5-(α-萘)-2H-四唑-2-乙酰肼(Ⅰ)与芳酰基异硫氰酸酯缩合制得16种新的1-[5-(α-萘)-2H-四唑-2-乙酰基]-4-芳酰基胺基硫脲(Ⅱ),(Ⅲ)在碱性催化条件下环化为3-[5-(α-萘)-2H-四唑-2-亚甲基]-4-芳酰基-1,2,4-三唑啉-5-硫酮(Ⅲ),化合物的结构经元素分析,IR、~1H NMR和MS鉴定,对化合物(Ⅲ)的质谱裂解进行分析,解释了化合物(Ⅱ)的环化方向,经初步筛选,发现个别化合物对小麦胚芽生长有促进作用。 相似文献
55.
Novel illustrations of the specific reactivity of 1,1-diamino-2,2-dinitroethene (DADNE) leading to new unexpected compounds 总被引:2,自引:0,他引:2
1,1-Diamino-2,2-dinitroethene (DADNE) was further investigated and evaluated in oxidation and azidation reactions. DADNE gave new unexpected products as a result of its specific reactivity as previously observed. The X-ray structure determination was the key of success in this work enabling us to perfectly characterise the new products and argue about the reaction mechanisms as well. Once again, the nucleophilic gem-dinitrocarbon of DADNE seemed to be directly involved in these transformations. Attempts to change the regioselectivity were performed by modifying the experimental conditions. 相似文献
56.
Hossein A. Dabbagh Alireza Najafi-Chermahini Soodabeh Banibairami 《Tetrahedron letters》2006,47(23):3929-3932
The synthesis and characterization of 5-(1-(2-(1H-tetrazole-5-yloxy)naphthalen-1-yl)naphthalen-2-yloxy)-1H-tetrazole (BIZOL) as the first bis-tetrazole BINOL-type ligands is described. 相似文献
57.
<正>An efficient route for the synthesis of 5-substituted 1H-tetrazole via[2+3]cycloaddition of nitriles and sodium azide is reported usingγ-Fe_2O_3 nanoparticles as a magnetic separable catalyst.Under optimized conditions,the moderate to good yields(71-95%) can be obtained.The catalyst can be easily separated by a magnet and reused for several circles. 相似文献
58.
Vyacheslav Boyko Roman Rodik Oksana Danylyuk Lyudmila Tsymbal Yaroslav Lampeka Kinga Suwinska Janusz Lipkowski Vitaly Kalchenko 《Tetrahedron》2005,61(52):12282-12287
The synthesis of new calix[4]arenes bearing two or four tetrazole liganting groups at the upper rim is decribed. The structures of tetrakis-tetrazolecalix[4]arene and its palladium dichloride (2:2) complex are examined by X-ray crystallography. 相似文献
59.
Tuoping Hu Longjie Liu Xiaoli Lv Xiaohui Chen Haiyan He Fangna Dai Guoqing Zhang Daofeng Sun 《Polyhedron》2010
Three metal-organic frameworks with 1D zigzag chain [Zn(dte)(H2O)3]·2H2O (1), 2D double layer [Cd(dtb)(H2O)(phen)] (2), 3D network [Zn(dte)(phen)] (3) based on tetrazole-based ligands (H2dtb = 1,3-dis(2H-tetrazol-5-yl)benzene, H2dte = 1,4-ditetrazolylethylene, phen = 1,10-phenanthroline), have been synthesized and characterized. All the compounds exhibit unusual strong luminescence at room temperature in the solid state and can be potentially used as luminescent materials. 相似文献
60.