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1.
The emerging interest of ferrocenyl diphosphines in metal complexes has led to some significant developments recently in the clusters, polymetallic aggregates and oligomers of 1,1-bis(diphenylphosphino)ferrocene (dppf). In this review, we shall focus on the synthetic strategies and the chemical, structural and bonding characteristics of these materials.  相似文献   

2.
3,4-Bis(α-nitroalkyl-ONN-azoxy)furazans and some of their derivatives   总被引:3,自引:0,他引:3  
Reaction of pseudonitroles and their derivatives with diaminofurazan in the presence of dibromoisocyanuric acid (DBI) resulted in symmetrical 3,4-bis(-nitroalkyl-ONN-azoxy)-furazans or their derivatives. For the synthesis of bis(nitroalkyl-ONN-azoxy)furazans bearing various a-nitroalkyl-ONN-azoxy groups, the method based on the reaction of ??-nitronitroso compounds with 3-amino-4-(nitroalkyl)-ONN-azoxy)furazans (in the presence of DBI) was developed. Synthetic procedures towards aforementioned compounds with nitromethyl-, dibromonitromethyl-, trinitromethyl-ONN-azoxy and other groups were described.  相似文献   

3.
IntroductionRecentresearcheffortshavebeendevotedtothestudyoflatetransitionmetalcomplexesasmodelsystemsforthepolymerizationoroligomerizationofethylene .1 3ThemostnotableachievementshavebeendonebyBrookhart,4 Bennett,5andGibsongroups .6,7Theyinde pendentlyrepor…  相似文献   

4.
5.

The title compound has been synthesized and characterized by elemental analysis and conductivity studies. The crystal and molecular structure has been determined. There are two different types of molecules in the crystal: mono- and diaquadi(acetato-O)-bis(2,4'-bipyridyl) copper (II). Both copper atoms occupy special positions. The copper atoms show almost ideal square pyramidal (4 + 1) and square bipyramidal (4 + 2) coordination. Due to the Jahn-Teller effect, the axial Cu-O(water) bond distances are longer than respective equatorial Cu-O(acetate) bond distances. The bond valences of the copper were computed. An intramolecular strong hydrogen bond linking O(water) and O(acetate) atoms exists in the molecule. The differences of geometrical environment for copper in mono- and diaquadi(acetato-O)-bis(2,4'-bipyridyl) copper(II) are imposed by strong intermolecular hydrogen bonds creating a linear infinite chain structure along crystallographic x axis. Also weak intramolecular hydrogen bonds are present in the molecule.  相似文献   

6.
1 INTRODUCTION Macrocyclic ligands and their metal complexes have received much attention due to their applications in ion transport, ion separation and as models in biomimic researches[1~7]. The synthetic methods of macrocyclic ligands and their metal complexes are mainly divided into three kinds[8]. The first one is synthesizing free ligand, then forming the metal complexes; the second is template synthesis; and the third is synthesizing the end-off or side-off precursor ligand, then c…  相似文献   

7.
1-Methyl and 1-benzyl 3,5-bis(-haloalkyl) isocyanurates were reacted with thiourea to obtain 1-methyl and 1-benzyl 3,5-bis[-[amino(imino)methylmercapto]alkyl] isocyanurates, respectively. Hydrolysis of the latter gave the corresponding 3,5-bis(-mercaproalkyl) izocyanurates.  相似文献   

8.
1 INTRODUCTION Two-photon absorption is a subject which attracts fast-growing interest in chemistry, photonics, and biological imaging fields in the past decades[1]. The two-photon techniques have wide applications, for example, optical power limiting[2], two-photon opti- cal memory[3], two-photon confocal imaging[4] and up-conversion laser[5]. Especially recently, the inte- rest has gradually been focused on studying two- photon initiated photopolymerization (TPIP) and exploring some pe…  相似文献   

9.
Reactions of 2-alkoxypropenals with α-hydroxyamino oximes in neutral medium involve the aldehyde group of the former to afford both acyclic and cyclic azomethine oxides: N-(2-hydroxyiminoalkyl)-N-(2-alkoxy-2-propenylidene)amine oxides and 1-hydroxy-2,5-dihydroimidazole 3-oxides. The state of tautomeric equilibrium between the cyclic and acyclic products depends on the solvent nature and temperature. The reaction in acidic aqueous medium is accompanied by hydrolysis of the vinyl ether moiety in 2-alkoxy-propenals with formation of 2-oxopropionaldehyde which reacts with α-hydroxyamino oxime at the hydroxy-amino group to give substituted pyrazine 1,4-dioxides. The reaction of 2-alkoxypropenals with 1,2-bis-(hydroxyamino)cyclohexane leads to formation of 2-(1-alkoxyvinyl)-1,3-dihydroxyperhydrobenzimidazoles. The structure of the products was proved by IR, UV, and 1H and 13C NMR spectroscopy and X-ray analysis.  相似文献   

10.
Superbasic properties of naphthalene protone sponges are determined by the p character of the unshared electron pair on the nitrogen atom of the dialkylamino group and by distortion of the n,* conjugation.  相似文献   

11.
Abstract

3,5-Bis(aminomethyl)pyrazole (Hbampz) forms binuclear copper(II) complexes of the formula [Cu2(bampz)2X2] (X = CI, Br). The crystal structure of [Cu2(bampz)2Br2] has been determined by the X-ray method: formula = CuBrN4C5H9, monoclinic, space group P21/n, a = 9.214(1), b = 10.078(1), c = 8.775(1) Å, β = 97.33(1)°, V = 808.1 Å3. Two bampz? molecules combine with two copper(II) ions via the pyrazolate nitrogen and aminonitrogen atoms in the side chains affording an essentially planar N4 environment for each metal ion. The Cu-Cu separation is 3.947(5)A. The axial site of each copper is weakly coordinated by a bromide ion with a Cu-Br distance of 2.895(4) A. Cryomagnetic investigations over the temperature range 80-300 K revealed a significant antiferromagnetic interaction through the pyrazolate bridges. The exchange integrals (J) based on the Heisenberg model (H =—2J?1.?2) was estimated at—200.8 and—192.0 cm?1 for [Cu2(bampz)2Cl2] and [Cu2(bampz)2Br2], respectively.  相似文献   

12.
Journal of Thermal Analysis and Calorimetry - The values of the standard molar energies of combustion of Tetra-N-phenylbenzidine and 4,4′-Bis(N-carbazolyl)-1,1′-biphenyl in solid phase...  相似文献   

13.
1-Alkyl 3,5-bis(-hydroxyalkyl) isocyanurates were reacted with mercaptoacetic acid to obtain 3,5-bis(-mercaptoacetoxyalkyl) isocyanurates whose oxidation gives rise to macrocyclic disulfides.  相似文献   

14.
A fluorescent Ni(II) complex 1, [Ni(OH-H2Bdc)(Bibimp)]n·nH2O, constructed with 5-hydroxyisophthalic acid(OH-H2Bdc) and 2,6-bis(2-benzimidazolyl)pyridine)(Bibimp) has been synthesized by hydrothermal methods and structurally characterized by elemental analysis, IR spectroscopy, TG/DTG, fluorescence spectrum and single-crystal X-ray diffraction. The title complex crystallizes in triclinic system, space group P1 with a = 10.187(2), b = 10.273(2), c = 13.401(3), α = 69.65(3), β = 69.66(3), γ = 70.61(3)o, V = 1196.8(4) 3, and Z = 2. The adjacent chains of complex 1 are stacked offset with respect to each other in an ABAB fashion by van der Waals interactions, and only a weak interlayer nonclassical C–H···O hydrogen bond has been observed. Complex 1 displays strong blue fluorescent emissions at 483 nm in the solid state upon photo-excitation at 365 nm at room temperature.  相似文献   

15.

Ni(II) complexes of composition [Ni(bziprdtc)(dppf)]X, [Ni(but2dtc)(dppf)]X and [Ni(Rdtc)(dppf)]X [bz = C7H7; ipr = C3H7; but = C4H9; R = pld = C4H8; tz = C3H6S; hmi = C6H12; dtc = S2CN; dppf = 1,1'-bis(diphenylphosphino)ferrocene C34H28P2Fe; X = ClO4, I, Br, NCS] were synthesized and characterized X-ray structural analysis of [Ni(hmidtc)(dppf)]ClO4 confirmed coordination number four for nickel in a distorted, square-planar, NiS2P2 arrangement  相似文献   

16.
Hydrochlorination of 1,2-bis(silyl)ethylenes of the general formula MenCl3-n SiCH = CHSiMen· Cl3-n , where n = 0-3, in the presence of FeCl3 was carried out. By NMR spectroscopy it was shown that in the case of the MeCl2Si derivative the major product is 1,1-bis(silyl)chloroethane and the minor product is its isomeric 1,2-bis(silyl)chloroethane (4:1). A reaction scheme is proposed, that includes isomerization of the intermediate bis(silyl)ethyl cation.  相似文献   

17.
Syntheses of diols of structure [HOCH2CH2S]2(CH2)n in 86–95% yield from the sodium salt of 2-mercaptoethanol and Br(CH2)nBr (n = 1 to 5) or in 60–90% yield from 2-chloroethanol and NaS(CH2)nSNa (n = 2 to 5) are described. The diol [HOCH2CH2SCH2CH2]2O was prepared in 82% yield from the sodium salt of 2-mercaptoethanol and [ClCH2CH2]2O, and in 88% yield from 2-chloroethanol and [HSCH2CH2]2O. Mono- and bis-sulfoxides and bis-sulfones of these species were prepared in generally high yield by treatment with an equivalent of KIO4 in aqueous methanol, two equivalents of NaIO4 in aqueous methanol, or four equivalents of H2O2 in trifluoroacetic acid respectively. The compounds are important analytical standards for investigating the fate of the chemical warfare agents sesquimustard Q and oxygen mustard T in environmental samples.  相似文献   

18.
1 INTRODUCTION The coordination chemistry of bithioethers with noble metal ions has received considerable attention for a very long time due to their appli- cations in extracting noble metals. A number of Pt(Ⅱ) complexes with such ligands have been reported[1~7], among which some crystal structures have been determined[4~7]. However, most of these structures are Pt(Ⅱ) complexes of a few bithioether ligands with flexible alkyl spacers, RS(CH2)nSR. To our knowledge, the crystal str…  相似文献   

19.
Coordination polymers of 1,4-bis(2′-hydroxyphenylazomethine) phenylene have been prepared with the metal ions Ti(III), Cr(III), Fe(III), Mn(II), Ni(II), and Cu(II). They were characterized by elemental analysis, IR, and electronic spectra. The metal contents in all polymers were found to be consistent with a 1:1 (metal:ligand) stoichiometry. The thermal behavior of these coordination polymers has been studied by thermogravimetric analysis in air up to 750°C, and the data showed that they are thermally stable up to 200°C. Physical properties such as the solubility and viscosity of the polymer complexes were also determined. Electrical conductivity measurements of the synthesized polychelated polymers showed that they are insulators except for the Ni(II) complex which shows a semiconducting character. Mössbauer data clearly establish the 3 + oxidation state for the iron complex polymer.  相似文献   

20.
1-Methyl or 1-benzyl 3,5-bis(-bromoalkyl) isocyanurates with the alkyl chain comprising 3 through 6 methylene units were synthesized by the reaction of disodium methyl and benzyl isocyanurates with ,-dibromoalkanes. The reaction of disodium methyl and benzyl isocyanurates with ethylene chlorohydrin was used to obtain 1-methyl or 1-benzyl 3,5-bis(2-hydroxyethyl) isocyanurates whose treatment with PBr3 or SOCl2 gave the corresponding 1-alkyl 3,5-bis(2-haloethyl) isocyanurates. 1-Methyl and 1-benzyl 3,5-bis-(chloromethyl) isocyanurates were prepared by treatment with SOCl2 of 1-methyl or 1-benzyl 3,5-bis(hydroxymethyl) isocyanurates obtained, in their turn, by condensation of methyl and benzyl isocyanurates with formaldehyde.  相似文献   

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