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11.
A new hexanuclear copper(Ⅱ) complex,[Cu 6 (DPPZ) 4 (btc) 4 (H 2 O) 8 ]·5H 2 O (1,DPPZ=dipyrido[3,2-a:2,3-c]phenazine,H 3 btc=1,3,5-benzenetricarboxylic acid),has been hydrothermally synthesized and structurally characterized by X-ray single-crystal diffraction,elemental analyses,IR,and thermogravimetric analysis.Its crystal structure is of triclinic system,space group P1 with a=12.489(4),b=14.234(5),c=14.484(5),α=82.848(4),β=79.399(4),γ=73.646(4)°,V=2421.2(13) 3,Z=1,Cu 6 C 108 H 78 N 16 O 37,M r=2573.17,D c=1.752 g/cm 3,μ=1.398 mm-1,F(000)=1308,GOOF=1.011,the final R=0.0495 and wR=0.1030 for 5420 observed reflections with I > 2σ(Ⅰ).In 1,four btc 3ligands act as bridges between six neighboring Cu atoms to form an unusual hexanuclear copper cluster.The clusters are further connected by two types of O-H···O and O-H···N hydrogen bonds,generating a three-dimensional supramolecular structure.In addition,intermolecular and intramolecular π-π stacking interactions further consolidate the three-dimensional supramolecular framework of 1. 相似文献
12.
将吡啶-2,4,6-三羧酸(2,4,6-pytaH3),4-氨基-3,5-二(4-吡啶基)-1,2,4-三氮唑(4,4′-abpt)和CoCl2在不同的pH条件下发生水热反应,得到2个新的配位聚合物[Co(2,4,6-pytaH)(4,4′-abpt)(H2O)](1)和[Co1.5(2,4,6-pyta)(4,4′-abpt)(H2O)3].3.5H2O(2)。配合物1是在吡啶-2,4,6-三羧酸酸性环境下产生的,吡啶-2,4,6-三羧酸在水热条件下只脱去2个羧基上的质子变成2,4,6-pytaH2-,而配合物2是在NaOH碱性溶液下反应得到的,其中吡啶-2,4,6-三羧酸完全脱去3个羧基上的质子变成2,4,6-pyta3-。配合物1中包含一维Co-羧酸链,2中存在具有(4,4)拓扑网络的二维层。1和2中的一维链和二维层通过π-π堆积和丰富的氢键作用分别拓展成三维超分子网络。单晶结构分析表明,配合物1结晶于单斜晶系,P21/n空间群,a=0.961 30(10)nm,b=0.632 09(6)nm,c=3.372 9(4)nm,β=95.104(2)°,V=2.041 3(4)nm3,Z=4。而配合物2结晶于单斜晶系,P21/c空间群,a=1.795 2(2)nm,b=0.729 62(8)nm,c=2.078 7(2)nm,β=112.323(2)°,V=2.518 6(5)nm3,Z=4。 相似文献
13.
Christian Neis Thomas Kradolfer Kaspar Hegetschweiler 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(6):632-637
Single crystals of (1,3‐diamino‐5‐azaniumyl‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)lithium(I) diiodide dihydrate, [Li(C6H16N3O3)(C6H15N3O3)]I2·2H2O or [Li(Htaci)(taci)]I2·2H2O (taci is 1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol), (I), bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)sodium(I) iodide, [Na(C6H15N3O3)2]I or [Na(taci)2]I, (II), and bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)potassium(I) iodide, [K(C6H15N3O3)2]I or [K(taci)2]I, (III), were grown by diffusion of MeOH into aqueous solutions of the complexes. The structures of the Na and K complexes are isotypic. In all three complexes, the taci ligands adopt a chair conformation with axial hydroxy groups, and the metal cations exhibit exclusive O‐atom coordination. The six O atoms of the resulting MO6 unit define a centrosymmetric trigonal antiprism with approximate D3d symmetry. The interligand O...O distances increase significantly in the order Li < Na < K. The structure of (I) exhibits a complex three‐dimensional network of R—NH2—H...NH2—R, R—O—H...NH2—R and R—O—H...O(H)—H...NH2—R hydrogen bonds. The structures of the Na and K complexes consist of a stack of layers, in which each taci ligand is bonded to three neighbours via pairwise O—H...NH2 interactions between vicinal HO—CH—CH—NH2 groups. 相似文献
14.
Henry Insuasty Braulio Insuasty Edison Castro Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(9):908-911
In the title compound, C15H12N4OS2, the bond distances in the fused heterocyclic system show evidence for aromatic‐type delocalization in the pyrazole ring with some bond fixation in the triazine ring. The thiophenyl substituent is slightly disordered over two sets of atomic sites having occupancies of 0.934 (4) and 0.066 (4). The non‐H atoms in the entire molecule are nearly coplanar, with the planes of the furanyl substituent and the major orientation of the thiophenyl substituent making dihedral angles of 5.72 (17) and 1.8 (3)°, respectively, with that of the fused ring system. Molecules are linked into centrosymmetric R22(10) dimers by C—H...O hydrogen bonds and these dimers are further linked into chains by a single π–π stacking interaction. Comparisons are made with some related 4,7‐diaryl‐2‐(ethylsulfanyl)pyrazolo[1,5‐a][1,3,5]triazines which contain variously substituted aryl groups in place of the furanyl and thiophenyl substituents in the title compound. 相似文献
15.
Saskia Menzel Konstantinos D. Demadis Christoph Janiak 《Phosphorus, sulfur, and silicon and the related elements》2020,195(10):830-835
AbstractThe fully deprotonated anion of 1,3,5-benzene-triphosphonic acid 1,3,5-C6H3[PO32?]3 gives rise to deceptively simple 1H and 31P NMR spectra due to a corresponding [AX]3 spin system. The 13C{1H} NMR spectrum reveals two 13C isotopomers which are identified via AXX′2 systems. Results from analysis and iteration are described. 相似文献
16.
Ultrasensitive detection of TNT in soil, water, using enhanced electrogenerated chemiluminescence 总被引:1,自引:0,他引:1
Tommie L. Pittman 《Analytica chimica acta》2009,632(2):197-32
The ultrasensitive detection of 2,4,6-trinitrotoluene (TNT) was accomplished on the basis of sandwich-type TNT immunoassay combined with electrogenerated chemiluminescence (ECL) technology. Biotinylated anti-TNT species were attached to the surface of 1-μm diameter streptavidin-coated magnetic beads (MB) and 10-μm diameter avidin-coated polystyrene microspheres/beads (PSB) pre-loaded with ECL labels (∼7 billion hydrophobic ruthenium(II) tris(2,2′-bipyridine) (RuII) molecules per bead) to form anti-TNT ↔ MB and anti-TNT ↔ PSB(RuII) conjugates, respectively. Sandwich-type PSB(RuII) ↔ anti-TNT < TNT > anti-TNT ↔ MB aggregates were formed when PSB(RuII) ↔ anti-TNT was mixed with anti-TNT ↔ MB conjugates in the presence of analyte TNT and 2.0% bovine serum albumin blocking agent. The newly formed aggregates were magnetically separated from the aqueous reaction media and dissolved in acetonitrile containing 0.10 M tri-n-propylamine ECL coreactant-0.055 M trifluoroacetic acid-0.10 M tetrabutylammonium tetrafluoroborate electrolyte. ECL as well as cyclic voltammetric measurements were carried out with a potential scan from 0 to 2.8 V vs Ag/Ag+, and the integrated ECL intensity was found to be linearly proportional to the analyte TNT concentration over the range of 0.10-1000 ppt (pg mL−1). The limit of detection (≤0.10 ± 0.01 ppb) is about 600× lower as compared with the most sensitive TNT detection method in the literature, and the absolute detection limit in mass (∼0.1 pg) is only ∼0.5% of that from mass spectroscopy. The approach coupled with the standard addition method was applied to measure the TNT contaminations in soil and creek water samples collected from a military training base. 相似文献
17.
One new hydrolyzable tannin, 1‐O‐[(E)‐p‐coumaroyl]‐3‐O‐galloyl‐β‐D ‐glucopyranose ( 1 ), was isolated from the rhizome of Balanophora harlandii, together with 18 known phenolic compounds. Their structures were determined by detailed spectroscopic analysis. Of the known compounds, 3‐O‐caffeoyl‐D ‐glucopyranose ( 6 ) was obtained as a natural product for the first time, and compounds 2 – 6 and 8 – 19 were identified for the first time from this plant. The radical‐scavenging activity of the isolated compounds was tested by a DPPH assay. 相似文献
18.
Svetlana N. Mikhaylichenko Saurabh M. Patel Aleksey A. Chesnyuk 《Tetrahedron letters》2009,50(21):2505-2508
We have studied the reaction of methylenedicarbonyl compounds with 4,6-disubstituted 2-hydrazinyl-1,3,5-triazine in order to obtain novel coupled biheterocyclic aromatic systems with potential bioactivity. Reaction conditions were studied and optimized, and a series of 4,6-disubstituted 2-(1H-pyrazolyl)-1,3,5-triazines were obtained with good yield. 相似文献
19.
Photocyclization of 2,4,6-triethylbenzophenones (TEBPs) into (E)- or (Z)-benzocyclobutenols ((E)- or (Z)-CBs) is E-selective in solution. By contrast, upon solid-state photolysis, TEBP-3,4-diCl and especially TEBP-4-t-Bu gave (Z)-CB relative to (E)-CB with a much higher proportion than that in solution. For TEBP-4-t-Bu, the most major product in the solid state is an indanol derivative (Inol) (E/Z/Inol=1:3.9:10.3 at 9% conversion). On the basis of the X-ray crystallographic analysis, Inol and (Z)-CB are both topochemical products. Notably, the relative proportion of (E)-CB increased with increased conversion, namely with increased disruption of the crystal lattice. The DFT calculation of highly hindered 2,6-diisopropylbenzophenone (DIBP) was also conducted. These results in conjunction with the previous results on 2,4,6-triisopropylbenzophenones (TIBPs) indicate that CB is formed either via trans-enol followed by its conrotatory ring-closure (paths a and d) or through direct cyclization of biradical (BR) (path b) as shown in Scheme 1. Normally the former route is faster. However, in the crystalline state or in the case of sterically hindered phenyl ketones, path b tends to be adopted. 相似文献
20.
The reaction of hexafluoro-cyclo-triphosphazene P3N3F6 with ammonia in acetonitrile has been studied. New compounds, (2-imino-2,4,4,6,6-pentafluoro-2λ5,4λ5,6λ5-cyclo-triphosphaza-1,3,5-trienyl)-2-amino-4,4,6,6-tetrafluoro-2λ5,4λ5,6λ5-cyclo-triphosphaza-1,3,5-triene, P3N3F5–NH–P3N3F4NH2 (2) and cis and trans isomers of non-gem-2,4-diamino-2,4,6,6-tetrafluoro-2λ5,4λ5,6λ5-cyclo-triphosphaza-1,3,5-triene, P3N3F4(NH2)2 (4, 5), were detected by GC/MS, and 31P NMR spectroscopy in reaction mixtures. X-ray diffraction analysis of P3N3F5–NH–P3N3F4NH2 (2) revealed two conformational polymorphs, 2A and 2B, the latter being built up of two different conformers that were further denoted as 2Ba (the same as the single conformer in 2A) and 2Bb. The compound 2 was characterized by spectroscopic methods and its 2D potential energy surface (PES) was described by density functional theory computations depending on two dihedral angles. The calculated PES spans over 30 kJ/mol in energy including 8 local minima and all first and second order saddle points. The occurrence of the two experimentally observed conformers 2Ba and 2Bb seems to be governed by crystal packing effects. 相似文献