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The synthesis and crystal structures of two novel semicarbazones and four gold(III) compound derivatives of these semicarbazones are presented. A pattern in the formation of the semicarbazones shows the association of Cl– ions held together by intra- and intermolecular forces. [AuCl4]? and [AuBr4]? anions are co-crystallised with these semicarbazone ligands, and the packing architectures revealed by a single-crystal X-ray diffraction analysis showed the different influences of the anions and the association of these chemical species by intermolecular forces on the crystal packing. Crystal engineering led to gold(III) compounds that are stabilised by relevant hydrogen bonding networks, which demonstrated their importance to the supramolecular organisation of the studied compounds. Interestingly, Cl???Br interactions are observed and contribute to the formation of the supramolecular structures. Elemental analysis data and spectroscopic properties in the solid state and solution are also described. 相似文献
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Synthesis,spectroscopic evaluation,molecular modelling,thermal study and biological evaluation of manganese(II) complexes derived from bidentate N,O and N,S donor Schiff base ligands 下载免费PDF全文
Manganese(II) complexes having the general composition Mn(L)2X2 (where L = 3‐bromoacetophenone semicarbazone, 3‐bromoacetophenone thiosemicarbazone, 1‐tetralone semicarbazone, 1‐tetralone thiosemicarbazone, flavanone semicarbazone or flavanone thiosemicarbazone and X = Cl? or ½SO42?) were synthesized. All the complexes were characterized using elemental analyses, molar conductance and magnetic moment measurements, and mass, 1H NMR, infrared, electron paramagnetic resonance and electronic spectral studies. The molar conductance of the complexes in dimethylsulfoxide lies in the range 10–20 Ω?1 cm2 mol?1 indicating their non‐electrolytic nature. All the complexes show magnetic moments corresponding to five unpaired electrons. The possible geometries of the complexes were assigned on the basis of electron paramagnetic resonance, electronic and infrared spectral studies. Some of the synthesized ligands and their complexes were screened for their antifungal activities against fungi Macrophomina phaseolina, Botrytis cinerea and Phoma glomerata using the food poison technique and their antibacterial activities against Xanthomonas campestris pv. campestris and Ralstonia solanacearum using the paper disc diffusion method. They showed appreciable activities. 相似文献
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Summary The chelation behaviour of the complexes of La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Y3+, Tb3+, Dy3+, Ho3+ with biologically active 2-Hydroxy-1-naphthaldehyde semicarbazone (HNAS) has been studied potentiometrically in 75% (v/v) dioxane-water medium at various ionic strengths. The method of Bjerrum and Calvin, as modified by Irving and Rossotti has been used to find out the values of n andpL. The formation constants of metal chelates and the values ofS
min have been calculated. The order of formation constants of chelates was found to be: La3+3+3+3+3+3+3+3+3+3+3+.
Physikochemische Untersuchungen zur Komplexierung von biologisch aktivem 2-Hydroxy-1-naphthaldehyd-Semicarbazon (HNAS) mit Lanthanoiden
Zusammenfassung Das Chelierungsverhalten von La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Y3+, Tb3+, Dy3+ und Ho3+ mit 2-Hydroxy-1-naphthaldehydsemicarbazon (HNAS) wurde potentiometrisch in 75% (v/v) Dioxan-Wasser bei verschiedenen Ionenstärken untersucht. Die Werte für n undpL wurden nach der Methode von Bjerrum und Calvin in der Modifikation von Irving und Rossotti bestimmt. Die Komplexbildungskonstanten der Metallchelate und die WerteS min wurden ermittelt. Die Reihung der Komplexbildungskonstanten war La3+相似文献3+ 3+ 3+ 3+ 3+ 3+ 3+ 3+ 3 3+.
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Jesús Valdés-Martínez Ruben A. Toscano Roberto Salcedo Raymundo Cea-Olivares Adrian Meléndez 《Monatshefte für Chemie / Chemical Monthly》1990,121(8-9):641-647
Summary The crystal and molecular structure of salicylaldehyde semicarbazone was obtained by single crystal X-ray diffraction. The O atom of the semicarbazone fragment isanti to the N atom of the hydrazinic group. The distribution of bond lengths in the semicarbazone fragment indicates delocalization of the -electrons. The crystal structure is stabilized by intra- and intermolecular hydrogen bonds.
Semicarbazone und Thiosemicarbazone, 12. Mitt.: Die Kristallstruktur des Salicylaldehyd-Semicarbazons
Zusammenfassung Die Kristallstruktur und die molekulare Struktur des Salicylaldehyd-Semicarbazons wurde über Einkristall-Röntgenstreuung ermittelt. Das O-Atom des Semicarbazonteils stehtanti zum N-Atom der Hydrazin-Gruppierung. Die Bindungslängen in der Semicarbazoneinheit zeigen eine Delokalisierung der -Elektronen an. Die Geometrie der Verbindung wird durch stabilisierende intra- und intermolekulare Wasserstoffbrückenbindungen bestimmt.相似文献
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1 INTRODUCTION The donor properties of pyridine N-oxide and its substituted derivatives to form metal complexes have been widely investigated[1~3]. The resulting comple- xes were used as drugs[4] and catalysts[5]. So far, there have been a few reports on the synthesis of Schiff base derived from picolinaldehyde N-oxide with se- micarbazone (PNOS Scheme 1) and its metal com- plexes. And crystal structures of the complexes of PNOS with Au(III)[6], Pd(II)[7] and Cu(II)[8] were re- … 相似文献
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《Journal of Coordination Chemistry》2012,65(12):1003-1019
4,6-Diacetylresorcinol serves as a starting point for the generation of multidentate S/N/O or O/N/O symmetrical chelating agents by condensation with thiosemicarbazide or semicarbazide to yield the corresponding bis(thiosemicarbazone) H4L1 or bis(semicarbazone) H4L2, respectively. Reaction of H4L1 and H4L2 with M(NO3)2·6H2O (M?=?Co or Ni) afforded dimeric complexes for H4L1 and binuclear complexes for H4L2, revealing the tendency of S to form bridges. The dimeric cobalt complexes of H4L1 are very interesting in that they contain CoII/CoIII, side/side, low-spin octahedral coordinated CoIII-ions and high-spin square-planar coordinated CoII-ions. These complexes have the general formula [(H2L1)2Co2(H2O) (NO3)]·nEtOH. Arguments supporting these anomalous CoII/CoIII structures are based on a pronounced decrease in their magnetic moments, elemental and thermal analyses, visible and IR spectra, as well as their unreactivity towards organic bases such as 1,10-phenanthroline (phen), 2,2′-bipyridine (Bpy), N,N,N′,N′-tetramethylethylenediamine (Tmen) and 8-hydroxyquinoline (oxine, Ox). The dimeric octahedral NiII complex [(H2L1)2Ni2(H2O)4]·3H2O showed higher reactivity towards phen and Bpy and formed adducts; [(HL1)Ni2(B)(H2O)5] NO3 (B?=?phen or Bpy). In the presence of oxine, the dimeric brown paramagnetic octahedral complex [(H2L1)2Ni2(H2O)4]·3H2O was transformed to the dimeric brick-red diamagnetic square-planar complex [(H3L1)2Ni2](NO3)2. The latter showed dramatic behavior in its 1H NMR spectrum in DMSO-d 6, which was explained on the basis of H+-transfer. By contrast, the binuclear NiII–H4L2 complex (11) showed higher reactivity towards phen, Bpy and oxine. These reactions afforded mixed dimeric complexes having the molar ratio 2?:?2?:?1 (NiII?:?H4L2?:?base). The binuclear CoII–H4L2 complex afforded an adduct with phen and trinuclear complexes with Bpy and oxine. All complexes were found to be unreactive towards Tmen. Structural characterization was achieved by elemental and thermal analyses, spectral data (electronic, IR, mass and 1H NMR spectra) and conductivity and magnetic susceptibility measurements. 相似文献
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Ellery R. Garbelini Manfredo Hörner Vinícius F. Giglio Aline H. da Silva Andersson Barison Fábio S. Nunes Prof. Dr. 《无机化学与普通化学杂志》2009,635(8):1236-1241
Pale‐green crystals of the title complex were prepared by reaction of 2‐formylpyridine semicarbazone (HCSpy) and nickel(II) perchlorate in boiling ethanol. The crystals are triclinic with the nickel ion in an octahedral arrangement, coordinated by two nitrogen atoms and one oxygen donor atom from each ligand molecule. The effect of coordination on bond lengths and angles was explored by comparison with the single‐crystal structure data of the free ligand HSCpy, which was collected as well. The assumed coordination mode was supported by 1H and 13C NMR spectroscopic data. A detailed analysis of the electronic properties, including semi‐empirical quantummechanical calculations is presented. Furthermore, the data obtained from magnetic susceptibility and EPR measurements are in accordance with a low‐spin d8 nickel(II) complex. 相似文献