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101.
The interaction of iodine as an cr-acceptor with a synthetic ligand,benzene-1,3-disulfonylamid-kriptofix[22](BDSAK) as a π-donor has been investigated spectrophotometrically in chloroform(CHCl3) and dichloromethane(DCM) solutions.The results of mole ratio plots and Job's method show the stoichiometry of complexation I2/BDSAK is 1:1.Stability constants have been calculated in various temperatures and thermodynamic parameters have also been determined from the temperatures dependence of the stability constants by using van't Hoff equation.The results indicate the iodine complex with BDSAK is enthalpy stabilized but entropy destabilized. 相似文献
102.
Hassan Keypour Mohammad Hasan Zebarjadian Majid Rezaeivala Mojtaba Shamsipur Hamid Reza Bijanzadeh 《Journal of solution chemistry》2014,43(7):1218-1231
Lithium-7 NMR spectroscopy was used to investigate the stoichiometry and stability of a Li+ complex with two new branched amines, 4,7-bis(2-pyridylmethyl)-4,7-diazadecane-1,10-diamine (L1) and 4,8-bis(2-pyridylmethyl)-4,8-diazaundecane-1,11-diamine (L2), in acetonitrile and nitromethane. A competitive 7Li NMR method was also employed to probe the complexation of Mn2+, Zn2+ and Cd2+ ions with L1 and L2 in the same solvent systems. The formation constants of the resulting complexes were evaluated from computer fitting of the mole ratio data with an equation that relates the observed chemical shifts to the formation constant. In both solvents, the stability of the resulting 1:1 complexes was found to vary in the order Cd2+ > Zn2+ > Mn2+ > Li+. 相似文献
103.
Seyyed Javad Sabounchei Mohammad Panahimehr Hamid Reza Khavasi Fateme Akhlaghi Bagherjeri Collete Boscovic 《Chemical Papers》2014,68(5):624-632
The reaction of dppm (1,1-bis(diphenylphosphino)methane) with 2-bromo-4-phenylacetophenone and benzyl bromoacetate in chloroform produces new phosphonium salts, [Ph2PCH2PPh2CH2C(O) C6H4Ph]Br (I) and [Ph2PCH2PPh2CH2COOCH2Ph]Br (II). By allowing the phosphonium salts to react with the appropriate base, the bidentate phosphorus ylides, Ph2PCH2PPh2=C(H)C(O)C6H4Ph (III) and Ph2PCH2PPh2=C(H)C(O)OCH2Ph (IV), were obtained. The reaction of these ligands with mercury(II) halides in dry methanol led to the formation of the mononuclear complexes {HgX2[(Ph2PCH2PPh2C(H)C(O)C6H4Ph)]} (X = Cl (V); X = Br (VI); X = I (VII)) and {HgX2[(Ph2PCH2PPh2C(H)COOCH2Ph)]} (X = Cl (VIII); X = Br (IX); X = I (X)). The FTIR and 1H, 31P and 13C NMR spectra were studied. The structure of compound III was unequivocally determined by the single-crystal X-ray diffraction technique. Single-crystal X-ray analysis of the {HgBr2[(Ph2PCH2PPh2C(H)C(O)C6H4Me)]} complex (XI) revealed the presence of a mononuclear complex containing the Hg atom in a distorted tetrahedral environment. In all complexes, the ylides referred to above were coordinated through the ylidic carbon and the phosphine atom. 相似文献
104.
Ramin Ghorbani-Vaghei Zahra Toghraei-Semiromi Rahman Karimi-Nami 《Comptes Rendus Chimie》2013,16(12):1111-1117
A series of 2-amino-3-cyanopyridines were obtained from aryl aldehydes, substituted acetophenones, malononitrile and ammonium acetate in good to excellent yields by proceeding through a simple, mild and efficient procedure utilizing N,N,N′,N′-tetrabromobenzene-1,3-disulfonamide [TBBDA] and poly(N-bromo-N-ethylbenzene-1,3-disulfonamide) [PBBS] as catalysts. 相似文献
105.
The combination of aromatic aldehydes, and 1,3-dicarbonyl compounds in the presence of a catalytic amount of poly(N,N′-dibromo-N-ethyl-benzene-1,3-disulfonamide) [PBBS] and N,N,N′,N′-tetrabromobenzene-1,3-disulfonamide [TBBDA] leads to the formation of highly substituted tetrahydropyridines. In this way, a series of pharmacologically interesting substituted piperidine derivatives were obtained in moderate to high yields at room temperature. 相似文献
106.
Hassan Keypour Maryam Shayesteh Sadegh Salehzadeh Laura Valencia 《Journal of organometallic chemistry》2008,693(19):3179-3187
Two new potentially hexadentate N2O4 Schiff base ligands 2-((z)-(2-(2-(2-((z)-3,5-di-tert-butyl-2-hydroxybenzylideneamino) phenoxy) phenoxy) phenylimino) methyl)-4,6-di-tert-butylphenol [H2L1] and 2-((z)-(2-(2-(2-((z)-3,5-di-tert-butyl-2-hydroxybenzylideneamino) phenoxy)-5-tert-butylphenoxy) phenylimino) methyl)-4,6-di-tert-butylphenol [H2L2] were prepared from the reaction of 3,5-di-tert-butyl-2-hydroxy benzaldehyde with 1,2-bis(2′-aminophenoxy)benzene or 1,2-bis(2′-aminophenoxy)-4-t-butylbenzene, respectively. From the direct reaction of ligands [H2L1] and [H2L2] with copper(II) and cobalt(II) salts in methanolic solution and in the presence of N(Et)3 the neutral [CuL1], [CuL2], [CoL1] and [CoL2] complexes were prepared. All complexes were characterized by IR spectra, elemental analysis, magnetic susceptibility, mass spectra, molar conductance (Λm), UV-Vis spectra and in the case of [CuL2] with X-ray diffraction. X-ray crystal structure of [CuL2] showed that the complex contains copper(II) in a distorted square planar environment of N2O2 donors. Three CH/π interactions were observed in the molecular structure of latter complex. 相似文献
107.
The charge–transfer (CT) complex of donor antipyrine with Π‐acceptor 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) has been investigated spectrophotometrically in different halocarbon and acetonitrile solvents. The results indicated immediate formation of an electron donor–acceptor complex (DA), which is followed by two relatively slow consecutive reactions. The pseudo–first‐order rate constants for the formation of the ionic intermediate and the final product at various temperatures were evaluated from the absorbance–time data. The activation parameters, viz. activation energy, enthalpy, entropy, and free energy of activation, were computed from temperature dependence of rate constants. The stoichiometry of the complex was found to be 1:1 by Job's method of continuous variation. The formation constants of the resulting DA complexes were determined by the Benesi–Hildebrand equation at four different temperatures. The enthalpies and entropies of the complex formation reactions have been obtained by temperature dependence of the formation constants using Van't Hoff equation. The results indicate that DDQ complexes of antipyrine in all solvents are enthalpy stabilized but entropy destabilized. Both the kinetics of the interaction and the formation constants of the complexes are dependent upon the polarity of the solvents. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 45: 81–91, 2013 相似文献
108.
H. Keypour A. A. Dehghani-Firouzabadi M. Rezaeivala H. Goudarziafshar 《Journal of the Iranian Chemical Society》2010,7(4):820-824
A new pendant armed Schiff base macrocyclic complex of [CdL]2+, was prepared via cyclocondensation of 2,6-bis(2- formylphenoxymethyl)pyridine with branched hexaamine in the presence of Cd(II) ion. The ligand was 23-membered oxaazamacrocycle having two 2-aminoethyl pendant arms [L: 3,28-dioxa-14,17-bis(aminoethyl)-11,14,17,20,34- pentaazatetracyclo[34.3.1] tetratriacontane-1(34), 4, 6, 8, 10, 20, 22, 24, 26, 30, 32-undecaene]. The complex was investigated by IR, 1H NMR, microanalysis and MALDI mass spectroscopy. The structure of the complex was verified by ab initio HF-MO calculations using a standard 3-21G* basis set. This article introduces an unusual seven-membered chelate ring and shows that by its using, the Cd-N bonds lengths within the macrocycle would be longer and also Cd(II)-pendant amine bonds lengths would be shorter. 相似文献
109.
M. Torabbeigi T. Madrakian A. Afkhami 《Journal of inclusion phenomena and macrocyclic chemistry》2010,67(1-2):127-132
The spectrophotometric kinetic charge–transfer complex formation of iodine trichloride (ICl3) with Dibenzo-18-crown-6 (DB18C6), Dicyclohexyl-18-crown-6 (DC18C6) has been studied in chloroform; dichloromethane and propylene carbonate solutions at different temperatures. The results indicated immediate formation of an electron donor–electron acceptor complex; which is followed by two relatively slow consecutive reactions. The pseudo-first-order rate constants for the formation of the ionic intermediate and the final product have been evaluated at various temperatures by computer fitting of the absorbance–time data to appropriate equations. The influences of both the crown’s structure and the solvent properties on the formation of donor–electron acceptor complexes and the rates of subsequent reactions are discussed. 相似文献
110.
The use of N-bromosuccinimide as a catalyst promoted the synthesis of polycyclic indolo[2,3-b]quinoline derivatives in good to high yields in the reactions of various aryl amines with indole-3-carbaldehyde at room temperature under mild conditions. 相似文献