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1.
The Schiff base compounds N,N′-bis(3,4-dimethoxybenzylidene)-2,2-dimethylpropane-1,3-diamine hydrate, (3,4-MeO-ba)2Mepn.H2O (1), and N,N′-bis(3,4-dimethoxybenzylidene)butane-1,4-diamine, (3,4-MeO-ba)2bn (2), with different central groups derived from 3,4-dimethoxybenzaldehyde are synthesized and characterized by elemental analysis, FT-IR and 1H NMR spectroscopy. The crystal structure of 1 is determined by single crystal X-ray diffraction. Each imino functional group (-C=N-) is coplanar with its adjacent benzene ring and the two benzene rings form a dihedral angle of 86.868(27)°. Title compound 1 crystallizes in the monoclinic space group P21/n with unit cell parameters: a = 9.0774(2) Å, b = 29.2138(5) Å, c = 8.5696(2) Å, β = 92.4756(14)°, V = 2270.41(8) Å3 and Z = 4.  相似文献   

2.
In this study four coordinated complexes of zinc(II) halides with a new symmetrical bidentate Schiff base ligand (2,5-MeO-ba)2En are synthesized and characterized. The metal to ligand ratio of the complexes is found to be 1:1 with the formula of Zn((2,5-MeO-ba)2En)X2 (X = Cl (1), Br (2), I (3)). The crystal structure of the Schiff base ligand (2,5-MeO-ba)2En is determined by X-ray crystallography from single crystal data. Also, the optimized geometries of the Schiff base ligand (2,5-MeO-ba)2En and its zinc(II) complexes are calculated using the density functional theory method (B3LYP/6-31G). The obtained structural parameters of (2,5-MeO-ba)2En are in agreement with the experimental data.  相似文献   

3.
New Mn(III) complexes with Schiff bases and dicyanamide are synthesized: [Mn(Salpn)N(CN)2] n (two polymorphous modifications, Ia and Ib), {[Mn(5-BrSalen)N(CN)2] · CH3OH} n (II), and [Mn(3-MeOSalen)N(CN)2(H2O)] (III), where SalpnH2 = N,N′-bis(salicylidene)-1,3-diaminopropane, 5-BrSalenH2 = N,N′-bis(5-bromosalicylidene)-1,2-diaminoethane, and 3-MeOSalenH2 = N,N′-bis(3-methoxysalicylidene)-1,2-diaminoethane. Complexes Ia, Ib, and II have the polymer structure in which the dicyanamide anion binds the paramagnetic Mn(III) complexes with the Schiff bases into one-dimensional chains. Unlike them, in complex III the monomer units containing water and the dicyanamide anion as terminal ligands form dimers due to hydrogen bonds. The study of the magnetic properties of complexes Ia and II shows a weak antiferromagnetic interaction between the Mn3+ ions through the dicyanamide bridges in these complexes.  相似文献   

4.
Some new Schiff bases, (Z)-4-amino-3-((E)-(R-methoxybenzylidene)hydrazono)-6-methyl-3,4-dihydro-1,2,4-triazin-5(2H)-one (R?=?2 (L2), R?=?3 (L3) and R?=?4 (L4)), were synthesized by the condensation reactions of 4-amino-3-hydrazinyl-6-methyl-1,2,4-triazin-5(4H)-one (L1) and corresponding methoxybenzaldehyde in a molar ratio 1:1.5 in high yields. The reaction of L2 and L4 with an excess amount of the corresponding aldehydes gave the unsymmetrical bis-Schiff bases (E)-3-((E)-(R-methoxybenzylidene)hydrazono)-4-((E)-R-methoxybenzylideneamino)-6-methyl-3,4-dihydro-1,2,4-triazin-5(2H)-one (R?=?2 (L22) and R?=?4 (L44)), respectively. Furthermore, the reaction of L2?CL4 with silver(I) nitrate in a molar ratio 2:1 led to the silver(I)-complexes with the general formula [Ag(Lx)2]NO3 (Lx?=?L2 (2), L3 (3) and L4 (4)). All synthesized Schiff base compounds and complexes were characterized by a combination of IR-, 1H-NMR spectroscopy, mass spectrometry and elemental analyses. In addition, the structures of L2, L4·CH3CN, L22·CH3OH and L44·CH3OH and complexes 2 and 4 were determined by X-ray diffraction studies.  相似文献   

5.
In this work, some phosphoramidothioates (PATs) with the general formula of (CH3O)2P(S)X and (CH3O)(CH3S)P(O)X, where, X = NH2 (1 & 6), NH(CH3) (2 & 7), N(CH3)2 (3 & 8), N(Et)2 (4 & 9), (CH3CH2O)2P(S)NH(CH3) (5) and (CH3CH2O)(CH3CH2S)P(O)NH(CH3) (10), were synthesized and characterized by 31P, 31P{1H}, 13C and 1H NMR spectroscopy. The ability of the compounds to inhibit AChE was predicted by PASS software (version 1.193). They were also experimentally evaluated by a modified Ellman??s assay. The structure-activity relationship (SAR) between IC50 and some physico-chemical properties such as lipophilicity (logP), electronic and steric effects of the compounds was studied. The logP values were experimentally determined by the shake-flask (gas chromatography) method. Inhibitory potency for the compounds 1?C10 was 1 (3.38 mM) > 2 (3.97 mM) > 3 (4.75 mM) > 4 (6.00 mM) > 5 (5.51 mM) > 6 (0.07 mM) > 7 (0.23 mM) > 8 (0.39 mM) > and 9 (0.55 mM) > 10 (0.51 mM), respectively. IC50 and logP parameters of the P=O moiety were more than the P=S moiety in PAT analogues.  相似文献   

6.
<正>1 X-ray crystallography Suitable single crystal of 2 was sealed in a thin-walled glass capillary, and data collection was performed at 293(2) K on a Bruker SMART diffractometer with graphite-monochromated Mo Kα radiation(λ = 0.71073 ). Suitable single crystals of 3and 4 were mounted under nitrogen atmosphere on a glass fiber, and data collection was performed at 133(2) K on a Bruker APEX2 diffractometer with graphite-monochromated Mo Kα radiation(λ = 0.71073 ). The SMART program package was used to determine the unit cell parameters. The absorption correction was applied using SADABS. The structures were solved  相似文献   

7.
Mercury(II) complex, [Hg((3,4-MeO-Bza)2En)I2] (I), where (3,4-MeO-Bza)2En = N,N′-bis(3,4-dimethoxybenzaldehyde)ethylenediimine, has been synthesized from the reaction of HgI2 with (3,4-MeO-Bza)2En in methanol as solvent at 50°C. It was characterized by elemental analysis (CHN), 1H-NMR spectroscopy and confirmed by single-crystal X-ray diffraction analysis. The complex I crystallizes in the monoclinic system, with space group P21/c, having one symmetry-independent Hg2+ ion coordinated in a distorted tetrahedral geometry by two N atoms of the Schiff base ligand and by two I atoms. The Schiff base ligand (3,4-MeO-Bza)2En acts as a chelating ligand and coordinates via two N atoms to the mercury center. It adopts an (E, E) conformation.  相似文献   

8.
Three mercury(II) complexes, [Hg((23-MeO-ba)2en)X2] (X = I (1), Br (2) and Cl(3)), and the ligand (23-MeO-ba)2en ((23-MeO-ba)2en = N,N′-bis(2,3-dimethoxybenzylidene)-1,2-diaminoethane) have been synthesized and characterized by elemental analyses, FT-IR and 1H NMR spectroscopy. The crystal and molecular structures of 1 and 2 were determined by X-ray crystallography from single-crystal data. The metal-to-ligand ratio was found to be 1:1. The mercury(II) center in 1 and 2 has a distorted tetrahedral geometry with HgN2I2 and HgN2Br2 chromophores, respectively. The Schiff base ligand (23-MeO-ba)2en acts as a chelating ligand, coordinating via the two nitrogen atoms to the mercury(II) center, and it adopts an E,E conformation. The coordination sphere of the mercury(II) center in 1 and 2 is completed by the two I and Br atoms, respectively. In complex 1 an inter-molecular non-classical hydrogen bond of the type C-H?O was found, while in complex 2 inter- and intra-molecular non-classical hydrogen bonds of the type C-H?X (X = O and Br) were found. The 1H NMR spectra of the complexes exhibit downfield as well as upfield shifts of the free ligand resonances, reflecting changes in the ligand’s geometry during its coordination.  相似文献   

9.
The Ni(II) complexes [Ni(L)2](ClO4)2 (1) and [Ni(L)2(NO3)2] (2), where L is the Schiff base ligand of 4,5,9,13,14-pentaaza-benzo[b] triphenylene, were synthesized and characterized by physico-chemical and spectroscopic methods. Nano-sized particles of (1) were prepared both by sonochemistry (3) and solvothermal (4) methods. NiO nanoparticles were obtained by calcination of the nano-structure complexes at 500 °C. The structures of the nano-sized compounds were characterized by X-ray powder diffraction and scanning electron microscopy. The thermal stabilities of the bulk complexes (1–2) and nano-sized particles (3–4) were studied by thermogravimetric and differential scanning calorimetry. The catalytic activities of complexes of (1–4) are reported. The free Schiff base and its Ni(II) complexes have been screened for antibacterial activities against three Gram-positive bacteria. The metal complexes are more active than the free Schiff base. Electrochemical studies show that the Ni complexes undergo irreversible reduction in MeCN solution.  相似文献   

10.
Reactions of ClMe2Si–Z–SiMe2Cl (Z = SiMe2 (1a), CH2 (1c), O (1e)) with Li2E (E = S, Se) yielded eight-membered ring compounds (SiMe2ZSiMe2E)2 (3ad) as well as acyclic oligomers (SiMe2ZSiMe2E)x of different chain lengths. If 1:1 molar mixtures of 1a, 1c or 1e and a diorganodichlorosilane, -germane or -stannane (R2MCl2) are reacted with Li2E (E = S, Se, Te), six-membered ring compounds Z(SiMe2E)2MR2 (4a7g) are formed exclusively. Five-membered rings Z2(SiMe2)2E (Z = SiMe2 (8ac), CH2 (9ac); E = S, Se, Te) are obtained starting from the tetrasilane ClMe2Si–(SiMe2)2–SiMe2Cl (1b) or the disilylethane ClMe2Si–(CH2)2–SiMe2Cl (1d) by treatment with Li2E. All products were characterized by multinuclear NMR spectroscopy (1H, 13C, 29Si, 119Sn, 77Se, 125Te, including coupling constants) and the effects of the different ring sizes towards NMR chemical shifts are discussed.  相似文献   

11.
Three new Schiff base complexes, namely [Mn(L)Cl] · H2O (1), [Co(L)Cl]2 · 2CH3COCH3 (2) and [Co(L)NCS]2 (3), where H2L = 2,2′-[propane-1,2-diylbis(nitriloeth-1-yl-1-ylidene)]diphenol, have been prepared and characterized. The syntheses of 1 and 2 have been achieved by reacting equimolar amounts of the respective metal chloride and the tetradentate Schiff base ligand (H2L). While the mononuclear Mn(III) complex 1 was obtained with MnCl2 in acetone medium, the same synthetic system yielded the binuclear Co(III) complex 2 in the presence of CoCl2. Dissolution of 1 and 2 followed by crystallization with ammonium thiocyanate in methanol yielded two isostructural phenoxo-bridged binuclear complexes, namely [Mn(L)NCS]2 (previously reported by us) and a new complex [Co(L)NCS]2 (3), respectively. All the complexes 13 have been characterized by microanalytical, spectroscopic, single crystal X-ray diffraction and other physicochemical studies. Structural studies reveal that 1 adopts a distorted tetragonal pyramidal geometry while 2 and 3 comprise dimeric Co(III) units with bridging phenolate oxygen atoms. All the complex units in 1–3 and the respective solvent molecules are held together by weak intermolecular H-bonding to constitute a supramolecular network in the solid state. The antibacterial activity of the complexes has been tested against some Gram(+) and Gram(?) bacteria.  相似文献   

12.
The synthesis of 1-(3-thienyl)-benzimidazol-2-ones (3 a and4), described in an earlier paper1, has been further investigated. The Na-salt of3 a is converted to a benzimidazolone substituted in position 3 (3 b). Dehydrogenation of the thiophene nucleus of3 a with chloranil yields5 a, which undergoes substitution in position 3 with Cl(CH2)2N(CH3)2 to give5 b. Monochlorination of5 a yields5 c, the structure of which is confirmed by1H-NMR-spectroscopy.5 d is obtained by reaction of the Na-salt of5 c with Cl(CH2)2N(CH3)2.   相似文献   

13.
A glycol ether modified precursor, [Nb{O(CH2CH2O)2}(OPri)3] (A) was prepared by the reaction of Nb(OPri)5 with O(CH2CH2OH)2 in 1:1 molar ratio in anhydrous benzene. Further reactions of A with a variety of internally functionalized oximes in different molar ratios, yielded heteroleptic complexes of the type, [Nb{O(CH2CH2O)2}(OPri)3?n{ON = C(CH3)(Ar)}n] (1–9) {where Ar = C4H3O-2, n = 1 [1], n = 2 [2], n = 3 [3]; C4H3S-2, n = 1 [4], n = 2 [5], n = 3 [6]; C5H4N-2, n = 1 [7], n = 2 [8], n = 3 [9]}. All the above derivatives have been characterized by elemental analyses, FT-IR, NMR (1H, 13C {1H}) and FAB mass studies. Spectral studies of 1–9 suggest the presence of mono- and bi-dentate mode of oxime moieties, in the solution and in the solid states, respectively. FAB mass studies indicate monomeric nature for 3 and dimeric nature for A. TG curves of A and 6 show their low thermal stability. Soft transformation of A and 3 to pure niobia, a and b, respectively have been carried out by sol–gel technique. The XRD patterns of niobia a and b suggest the formation of nano-size crystallites of average size of 10.8 and 19.5 nm, respectively. The XRD patterns also indicate the formation of monoclinic phase of the niobia in both the cases. Absorption spectra of a and b suggest energy band gaps of 4.95 and 4.39 eV, respectively.  相似文献   

14.
Reaction of [VO(OPr i )3] (1) with [O(CH2CH2OH)2] in 1:1 molar ratio in anhydrous benzene yield glycol-modified precursor, [VO{OCH2CH2OCH2CH2O}{OPr i }] (2). Further reactions of (2) with internally functionalized oximes in anhydrous benzene yield heteroleptic complexes of the type [VO{OCH2CH2OCH2CH2O}{ON=C(R)(Ar)}] (3–8) {where R=CH3, Ar=C4H3O-2 (3), C4H3S-2 (4), C5H4N-2 (5); and when R=H, Ar=C4H3O-2 (6), C4H3S-2 (7), C5H4N-2 (8)}. All these derivatives have been characterized by elemental analyses, molecular weight measurements and spectroscopic techniques. The crysoscopic molecular weight measurement as well as FAB mass study suggests dimeric nature of (2). However, FAB mass spectrum of (4), and the crysoscopic molecular weight measurements of (3), (4), (5) and (6) indicate the monomeric behavior of the oximato derivatives (3–8). Hexa-coordination around vanadium(V) has been proposed for both monomeric and dimeric derivatives. Sol–gel transformations of (1), (2) or (4) to vanadia [(a), (b) or (c), respectively] have been carried out at low sintering temperature (600 °C). The XRD patterns of (a), (b) or (c) indicate formation of a single orthorhombic phase in all the three cases. The SEM images suggest grain like [for (a) and (b)] and rod like [for (c)] morphology of the crystallites. IR, Raman spectra as well as EDX analyses indicate formation of pure vanadia. Absorption spectra of the vanadia (b) and (c) suggest energy band gaps of 2.53 and 2.65 eV, respectively.  相似文献   

15.
Synthesis of germatranes XGe(OCH2CH2)3N (1), quasigermatranes X2Ge(OCH2CH2)2NR (R = H, Me) (2), and hypogermatranes X3Ge(OCH2CH2)NH2 (3) containing highly electronegative substituents at the Ge atom was described. An exchange reaction of the corresponding hydroxygermatranes with ammonium salts was used for their preparation. The synthesized compounds 1–3 were studied by IR spectroscopy.  相似文献   

16.
The Schiff base bis(4-ethylbenzyl) p-phenylenediimine, 4-eb-p-phen (1), and six new dimeric Pd(II) complexes of the type [Pd(μ-X)(4-eb-p-phen)]2 {X = Cl (2), Br (3), I (4), N3 (5), NCO (6), SCN (7)} have been synthesized and characterized by elemental analysis, IR spectroscopy, and 1H and 13C{1H}-NMR experiments. The thermal behavior of the complexes 27 has been investigated by means of thermogravimetry and differential thermal analysis. From the final decomposition temperatures, the thermal stability of the complexes can be ordered in the following sequence: 3 > 4 > 7 > 2 ≈ 5 > 6. The final products of the thermal decompositions were characterized as metallic palladium by X-ray powder diffraction (XRD).  相似文献   

17.
范宏 《高分子科学》2014,32(7):854-863
This contribution reports ethylene polymerization behavior of titanium complexes incorporating bis(phenoxyimine) ligands. Six phenoxy-imine Ti(IV) complexes {6-R1-2-[CH=N(2,6-difluoro-3,5-diR2-4-R3Ph)]C6H3O}2TiCl2(1: R1 = H, R2 = H, R3 = H; 2: R1 = H, R2 = H, R3 = 4-vinylphenyl; 3: R1 = CH3, R2 = H, R3 = H; 4: R1 = CH3, R2 = H, R3 = 4-vinylphenyl; 5: R1 = CH3, R2 = F, R3 = H; 6: R1 = CH3, R2 = F, R3 = 4-vinylphenyl) have been synthesized and evaluated for ethylene polymerization using dried MAO(simplified as DMAO) as cocatalyst. An obvious catalytic heterogeneity of Cat 2(Complex 2/DMAO) towards ethylene polymerization was observed, which was illustrated by decreased activity, multimodal molecular weight distribution and partially improved particle morphology comparing with Cat 1. Moreover, Cat 3 exhibits "living" characteristics in the process under certain conditions(25 °C, less than 20 min). Otherwise, the moderate to high ethylene polymerization activity of ca. 105-106 g PE/(mol Ti·h) and high molecular weight(Mw = 105-106) of polyethylene can be obtained by changing the skeleton structure of these complexes.  相似文献   

18.
A symmetric tetradentate Schiff base ligand, N,N′-bis(5-bromosalicylaldehyde)-1,3-phenylenediamine [(Brsal)2-1,3-phen) and its Cu(II) and Co(II) complexes with general formula M2((Brsal)2-1,3-phen)2, where M=Co (1) and Cu (2)], have been synthesized and characterized by elemental analyses and FTIR spectroscopy. In addition, Schiff base ligand has been characterized by 1HNMR spectroscopy. Thermogravimetric analysis of the ligand and its metal complexes reveals their thermal stability and decomposition pattern.  相似文献   

19.
Ten new N-nicotinyl and N-isonicotinyl phosphoramidates with formula XP(O)R2, X?=?Nicotinamide(nia), R?=?NHCH2Ph (1), N(CH3)CH2Ph (2), NHCH(CH3)Ph (3), NH-CH2C4H3O (4), NHCH2(C5H4N) (5), 3-NH-C5H4N (6), and YP(O)R2, Y?=?isonicotinamide(iso), R?=?NHCH2Ph (7), N(CH3)CH2Ph (8), NHCH(CH3)Ph (9), NH-CH2C4H3O (10) plus one new Er(III) complex with formula Er(L)2(NO3)3 (11), L?=?(iso)PO(NHCH2C4H3O)2 (10), were synthesized and characterized by elemental analysis and 1H, 13C, 31P NMR, IR, UV?Cvis spectroscopy. Crystal structures of compounds 10 and 11 were also determined by X-ray crystallography. Interestingly, the 1H NMR spectra of compounds 1, 2, 6, 7, 9 indicated long-range n J P,H (n?=?5,6,7) coupling constants, in the range of 1.4?C1.9?Hz, for the splitting of pyridine ring protons with phosphorus atom. IR results showed that the ??(C=O) values of compounds 7?C10 are greater than those of compounds 1?C5 which means that isonicotinyl moiety is more electron withdrawing than nicotinyl group. X-ray outcomes revealed that in complex 11 three phosphoric triamide ligands have been connected to each Er(III); one from Npyridine and two from P=O donor sites. One of the P=O donor ligands is mono dentate while the other one acts as a bidentate ligand and coordinates to another Er atom via its Npyridine site. By forming complex 11 the P=O and C?CNamide bond lengths of ligand is increased in both, mono and bi dentate, ligands while the C=O bond length is decreased to lower values. These variations are in good agreement with IR results. All H-bonds and electrostatic interactions lead to form a three-dimensional polymeric cluster in the crystal lattice of 10 and 11.  相似文献   

20.
The thermal decomposition reactions of CH3CH2C(CH3)2COOAg (1), (CH3)3SiCH2COOAg (2), CF3COOAg (3), (CH3)3CCOOAg (4), C2H5COOAg (5), C3F7COOAg (6), C6F13COOAg (7) and (CF2)3(COOAg)2 (8) were studied in N2 atmosphere using thermogravimetry (TG), derivative thermogravimetry and differential thermal analysis. Characterized compounds decomposed in one- or multi-step processes with metallic silver formation in the range 215–465 °C. TG-IR studies of gases evolved during thermolysis revealed products of decomposition, such as carboxylic acids, CO2 and recombination reactions.  相似文献   

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