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1.
Abstract The synthesis and mesomorphic properties of a class of cyclotriphosphazenes containing cyanostilbene groups with different terminal substituents (-H, -CH3, -OCH3, -CN) are described. All the resulting compounds are characterized by 1 H, 13 C, and 31P NMR, matrix-assisted laser desorption/ionization time of flight, and elemental analysis. The thermal behaviors of cyclotriphosphazene derivatives are studied by the means of differential scanning calorimetry and polarizing optical microscopy. Nematic phases are observed in cyclotriphosphazenes with terminal substituents (-CH3, -OCH3, -CN). 相似文献
2.
A. Mobinikhaledi N. Foroughifar M. Fallah 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):717-721
Benzoxazoles are of special interest because of having various types of biological properties such as antihistaminic, antihelmintic antifungal and antibacterial activities. 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 Benzamide derivatives, as the possible metabolites of benzoxazoles, show various types of biological activities. 11 , 12 Some N-(2-hydroxyphenyl)- benzamides, which showed significant activity compared to phenylacetamides and furamides,11 have been synthesized by treating 2-aminophenol with carboxylic acid chlorides under weak basic solution. 11 , 12 However, synthesis and especially biological activity of N-(3-hydroxy-2-pyridyl)benzamides were not studied well. Owing to the versatility of benzamides we have extended the reaction of 2-amino-3-pyridinol with different carboxylic acid chlorides in order to preparation of some new benzamide derivatives containing a hydroxypyridyl ring. 相似文献
3.
《Journal of Coordination Chemistry》2012,65(10):1621-1636
AbstractThe synthesis and spectral characterizations of [CdLCl2] (1) and [CdL(NO3)2(H2O)] (2) pincer complexes of the s-triazine core ligand (L), 2,4-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine), are presented. Complexes 1 and 2 have five- and eight-coordinated Cd(II) ions, respectively, where L acts as a neutral tridentate N-chelate. The coordination sphere is completed by two coordinated Cl– anions in 1 and with one water molecule and two bidentate nitrate anions in 2. The neutral complex units of 1 and 2 are packed by the polar Cl…H and O…H hydrogen bonds, respectively. Using Hirshfeld analysis, the percentages of these contacts are 24.5% and ~36.8%, respectively. Both complexes showed some anion-π stacking interactions. Thermogravimetric analysis showed that 1 is thermally more stable than 2. The orbital-orbital interactions included in the Cd-Cl, Cd-O, and Cd-N coordinate bonds were analyzed using DFT calculations. The calculated NMR results correlated very well with the experimental data. 相似文献
4.
Abstract α,α‐Dibromoketones (2) have been found to be a superior alternative to the conventionally used α‐bromoketones (1) for performing the Hantzsch thiazole synthesis.1 These crystalline, nonlachrymatory compounds are more reactive than 1 as demonstrated by their reaction with 3,5‐dimethyl‐1‐thiocarboxamide (5). 相似文献
5.
ω‐Isonitrosoacetophenone 1, phenylglyoxime 2, chlorophenylglyoxime 1, dopaminophenylglyoxime 3 and [(salen/saloph)Fe]2O 4 have been synthesized as described in the literature procedure. [Fe(III)(salen/saloph)dopaminophenylglyoxime)] (starting complexes) have been synthesized from dopaminophenylglyoxime and tetradentate schiff bases which contain dinuclear Fe(III) oxygen‐bridges N,N′‐bis(salicylidene)ethylenediamine (salenH2) and bis(salicylidene)‐o‐phenylenediamine (salophH2). The new heterotrinuclear complexes have been obtained from starting complexes and Co(II), Ni(II), Cu(II) salts. Then, heterotrinuclear vic‐dioxime complexes containing BF2 + capped have been synthesized. The complexes have been characterized as low‐spin distorted octahedral Fe(III) bridged by o‐hydroxyphenolic groups. The o‐hydroxyphenolic groups play a role as bridges for weak antiferromagnetic intramolecular exchange. The structure of dioxime and its complexes were identified by using elemental analysis, ICP‐AES, 1H‐NMR and IR spectral data. 相似文献
6.
Ali Ramazani Aram Rezaei Amir Mahyari Morteza Rouhani Mehdi Khoobi Elham Yaaghubi 《合成通讯》2013,43(10):1444-1454
Abstract Addition of an isocyanide to an iminium ion intermediate that forms from the reaction between a heteroarylcarbaldehyde and a secondary amine leads to formation of sterically congested 2-(heteroaryl)acetamide derivatives in the presence of silica gel at room temperature. The structures of the products were deduced from their 1 H NMR, 13 C NMR, and infrared spectra and mass spectrometry.
ACKNOWLEDGMENT
This work was supported by the Iranian National Science Foundation. 相似文献7.
《Journal of Coordination Chemistry》2012,65(17):2837-2851
A series of Co(II) azamacrocyclic complexes, 12aneN4, 14aneN4, Bzo2 12aneN4 and Bzo2 14aneN4, have been encapsulated in the nanocavity of zeolite-Y by a one pot template condensation reaction. Co(II) complexes with azamacrocyclic ligands were entrapped in the nanocavity of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of [bis(diamine)cobalt(II)], [Co(N–N)2]-NaY, in the supercages of the zeolite, and (ii) in situ condensation of the cobalt(II) precursor complex with diethyloxalate. The new host/guest nanocomposite materials (HGNM) have been characterized by FTIR, DRS and UV-Vis spectroscopic techniques, XRD and elemental analysis, as well as nitrogen adsorption. These complexes (neat and HGNM) were used for epoxidation of styrene with O2 as oxidant in different solvents. Electronic spectra of the reaction mixture indicated oxidation proceeds through a free radical mechanism. 相似文献
8.
《Journal of Coordination Chemistry》2012,65(10):1572-1583
Cobalt(II) chloro complexes were studied in aprotic solvents, namely, dimethylsulfoxide (DMSO), dimethylformamide (DMF), and propylene carbonate (PC). The measurements were performed spectrophotometrically in UV–visible–IR region at 25°C and at constant ionic strength: I = 1 mol L?1 in DMSO and DMF, and 0.1 mol L?1 in PC. Different models were tested and the model 1, 2, 3, 4, i.e., that of four mononuclear successive complexes was retained. Stability constants of the identified complexes were determined and they increase inversely with the Gutmann's donor number of the solvents. Calculated electronic spectra are reported and the effect of solvents on the spectral properties are discussed. The symmetry of tetrachlorocobaltate is strictly Td. 相似文献
9.
Anna Kovářová Vladimíra Novotná Milada Glogarová Miroslaw Salamonczyk Damian Pociecha 《Liquid crystals》2013,40(12):1501-1513
New liquid crystalline (LC) compounds containing the [2]benzothiophene chromophore unit have been synthesised and their mesomorphic properties studied. Mesomorphic and fluorescent properties have been modified by various chemical moieties. Among others, terminal fluoroalkyl and/or chiral chains were introduced to stabilise mesophases and support the formation of polar phases. In spite of the bent shape due to the central 1,3-diphenylbenzo[c]thiophene unit, all compounds exhibit phases typical for the rod-like LC: nematic, smectic A and smectic C or their chiral analogues using the chiral (S)-C2H5CH(CH3)(CH2)6CO or (S)-C10H21OCH(CH3)CO chain. The orientational order in the nematic phase was studied by polarised infrared measurements. The fluorescent properties of the studied compounds have been measured and their parameters established. 相似文献
10.
Sándor Kunsági-Máté Kornélia Szabó Előd L. Szabó István Bitter Géza Nagy László Kollár 《Supramolecular chemistry》2013,25(3):245-250
The π–π interaction-based inclusion complexation of calix[6]arene hexasulfonate as host with neutral aromatic guest molecules was studied in aqueous media. To vary the distribution of electron density on the guest's aromatic rings, the phenol parent compound was substituted in the para- or ortho- positions with CH3 group. To study the interaction between calixarene and the guests, PL, DSC and quantum-chemical methods were used. The results indicate 1:1 stoichiometry of the formed host-guest complexes. Although the enthalpy change during complex formation of calixarene with p- or o-cresol are the same, the Gibbs free energy change is significantly higher in the case of calixarene—o-cresol complexes. This property is due to the unexpected entropy change during the complex formation. Using molecular dynamic calculations, a guest-induced redistribution of the electron density on the calixarene rings, followed by the restructuring of the solvent molecules was identified as a background of this unexpected entropy change at molecular level. 相似文献
11.
Hamid Saeidian Seyed Esmaeil Hosseini 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):587-592
AbstractIsopropyl methylphosphonoselenofluoridate (sarin-Se) was synthesized in order to determine its analytical data and to compare them as well as its reactivity parameters with those of sarin. After synthesis, sarin-Se was characterized using 1H, 13?C and 31P NMR spectroscopy and high resolution mass spectrometry (HRMS). 1H and 13?C NMR chemical shifts were also calculated using density functional theory (DFT) and compared with experimental data, showing a close agreement. Electrophilicity indices of sarin and sarin-Se were calculated at B3LYP/6-31++G (2d, 2p) level of theory. HOMO-LUMO analysis provides a basis to explain electrophilic nature of sarin-Se and sarin, which are almost similar. Based on calculated data, 31P NMR chemical shift and the reactivity of sarin-Se towards some enzymes such as acetylcholinesterase and albumin were explained. 相似文献
12.
The facile synthesis of β-thioacrylates has been realized via direct three-component reactions of thiophenols, Wittig reagents, and acetyl chloride. Under transition metal-free conditions, a class of β-thioacrylates have been synthesized with fair to excellent yields via cascade C=C double bond and C(sp2)-S bond formation. 相似文献
13.
Sulekh Chandra Monika Tyagi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):778-789
A series of metal complexes of Pd(II), Pt(II), Rh(III), Ir(III), and Ru(III) with thiosemicarbazone and semicarbazone of 2-acetyl thiophene have been synthesized. Their structures were determined on the basis of elemental analyses; molar conductance; magnetic susceptibility measurements; and IR, 1 H NMR, and electronic spectral studies. On the basis of molar conductance, the complexes may be formulated as [M(L)2]Cl2 and [M′(L)2Cl2]Cl [where M = Pd(II), Pt(II) and M′ = Rh(III), Ir(III), and Ru(III)] due to their 1:2 and 1:1 electrolytic nature. On the basis of IR, 1 H NMR, and electronic spectral studies, an octahedral geometry has been assigned for Rh(III), Ir(III), and Ru(III), while square planar geometry has been assigned for the Pd(II) and Pt(II) complexes. The synthesized ligands and their complexes have been screened for bactericidal activity against several bacterial species (i.e., B. macerans, A. aureus, E. coli), and it is shown that the metal complexes act as more active antimicrobial agents than the uncomplexed ligands from which they derive. 相似文献
14.
Yann Vaugeois Ahmed Mazzah Roger Jaeger Jean Habimana 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1819-1840
Condensation reactions of 1,1,3,3,3 pentamethyldisiloxane-ol (MDH), in toluene catalysed by two[9.5pc] types of phosphonitrilic catalyst bearing a phosphazene ─N═PCl3, were studied using sampling and gas chromatographic analysis method. The condensation kinetics reactions were compared for both phosphazene compounds. The process is selective, leading to linear decamethyltetrasiloxane MD2M, (where D denotes the dimethylsiloxane unit and M denotes the trimethyloxysilane unit) as almost the exclusive primary product. The mechanisms of the MDH condensation are discussed using the 31 P NMR sampling technique. 相似文献
15.
K. Boukallaba A. Elachqar A. El Hallaoui A. Alami S. El Hajji B. Labriti 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):819-823
α-heterocyclic α-aminophosphonates were obtained in good yields by N-of several nitrogen heterocycles with α-azido-α-aminophosphonate 1. 1 相似文献
16.
《Journal of Coordination Chemistry》2012,65(5):825-832
A dicopper complex of p-tert-butylcalix8arene bearing eight salicylaldehyde acylhydrazone domains was prepared and its single crystal structure determined, in which only four acylhydrazone domains act as monoanionic tridentate planar chelators to coordinate to two copper ions. 相似文献
17.
Ruliang Xie Ting Zhang Qianfei Zhao Tao Zhang Xiangdong Mei Huizhu Yuan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1095-1103
Abstract A series of novel symmetric S,S′-2,2′-(ethane-1,2-diylbis(azanediyl)) bis(2-oxoethane-2,1-diyl) O,O,O′,O′-tetraethyl diphosphorodithioate derivatives (12) was designed and synthesized based on the cluster effect and the multiple binding sites of acetylcholinesterase (AChE). The structures of all the newly synthesized title compounds were characterized by 1 H and 13 C NMR as well as elemental analyses. Their inhibitory activities against AChE were tested, and compound 12b exhibited the best activity (6.60-fold higher than ethion). The results suggested that the compound would bind to the catalytic center and the narrow gorge of the AChE simultaneously. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional table. 相似文献
18.
《合成通讯》2013,43(18):2903-2910
ABSTRACT A reinvestigation of the recently described method of synthesis of highly substituted 1,6-naphthyridines was carried out. It was found out that the reaction of chalcones with malononitrile catalysed by pyrrolidine afforded the mixture of four products both when thermal as well as microwave heating was used. The claimed[1] 1,6-naphthyridines formation were exceptions. 相似文献
19.
《Green Chemistry Letters and Reviews》2013,6(3):475-479
Abstract 2,10-Dichloro-12-trichloromethyl-6-substituted xanthato-12H-dibenzo[d,g] [1,3,2] dioxaphosphocin-6-sulfides (2a–l) with the eight-membered phosphorus and oxygen heterocyclic ring were synthesized by reacting equimolar quantities of alcohols, carbon disulfide, and 2,6,10-trichloromethyl-12H-dibenzo[d,g][1,3,2] dioxaphosphocin-6-sulfide 1 in the presence of dimethylaminopyridine (DMAP). The structures of the products were confirmed by IR, 1H, 13C, 31P-NMR, and mass spectral analyses. 相似文献
20.
《Journal of Coordination Chemistry》2012,65(16-18):2557-2568
AbstractReaction between (E)-2-((pyridin-2-ylimino)methyl)phenol (HL) and copper(II) nitrate provides tetrakis{(E)-2-((pyridin-2-ylimino)methyl)phenolato}(hydroxido)0.5(nitrato)1.5-tetracopper(II) nitrate hydroxide, [(CuL)4(NO3)1.5(OH)0.5](NO3)(OH) (1). ESI-mass spectra show the ion peaks for the dinuclear species at m/z 565 for [(CuL)2(HCO2)]+ and 521 for [(CuL)2+H]+ and the mononuclear species at m/z 260 for [(CuL)]+. Vibrational spectra show very strong bands at 1604/1546?cm?1 for ν(C?=?N/C?=?C) and at 1384, 1351?cm?1 for ν(NO3–). Cyclic voltammograms demonstrate an irreversible redox processes for the Cu(II)/Cu(I) and Cu(I)/Cu(0) couples in acetonitrile. X-ray molecular structure determination explores the formation of a cationic tetranuclear copper(II)-complex, in which a deprotonated ligand molecule chelates to one copper ion with the phenolate-O and imino-N atoms. In addition, a phenolate-O atom bridges between two neighboring copper ions and a pyridine-N atom coordinates to a third copper ion, so that each ligand bridges among three copper ions in a κ2N,O:κO:κN' coordination sphere. Thus, the four copper ions and four chelating-bridging ligands assemble primarily into a cationic [(CuL)4]4+ complex. The two copper ions are further coordinated by either a nitrate anion (75% occupancy) or a hydroxide anion (25% occupancy) and form the core of a tetranuclear [(CuL)4(NO3)1.5(OH)0.5]2+ cation. 相似文献