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1.
Zusammenfassung Die Synthesen von [N2H5]2TiF6, [N2H5]2TiF6 · 2 HF und N2H6TiF6 sind beschrieben, die thermischen Eigenschaften, die Infrarotspektren werden diskutiert. Eine Disproportionierung von Hydrazin in Stickstoff und Ammoniak wurde festgestellt. Die Zuordnung der Infrarotbanden (4000–250 cm–1) deutet bei den ersten zwei Verbindungen auf die Hydrazinium1+-Verbindungen hin.
The synthesis and some thermal and structural properties of hydrazinium fluorotitanates(IV)
The synthesis of [N2H5]2TiF6, [N2H5]2TiF6 · 2 HF and N2H6TiF6 is described. The thermal properties and infrared spectra of the obtained compounds are discussed. Disproportionation of hydrazinium into nitrogen and ammonia is observed. The assignation of the bands in infrared spectra [4000 to 250 cm–1] of the first two compounds is consistent with the presence of hydrazinium1+ ion.


Mit 2 Abbildungen  相似文献   

2.
The infrared, Raman and inelastic neutron scattering (INS) spectra of TSA·6H2O and TPA·6H2O are in agreement with those expected for the presence of H5O+2 ions. Force fields for different assignment schemes are compared with the observed vibrational frequencies and the INS spectral profile. All but two schemes are eliminated. Whilst low-resolution INS spectroscopy cannot distinguish between these two schemes, the orientations of the vibrational ellipsoids for one scheme are in better agreement with those reported from low-temperature crystallographic studies of the H5O+2 ion.  相似文献   

3.
Two different hydrogen-bonded inclusion compounds, [2,4,6-C5H2N(COO?)3]0.5·[C(NH2) 3 + ]0.5·[(C2H5)4N+]·2H2O (1) and [2,4,6-C5H2N(COO?)3]·[C(NH2) 3 + ]·[(C2H5)4N+]·[(C3H7)4N+]·6H2O (2) are reported in this paper, in which 2,4,6-pyridine-tricarboxylic anions, guanidiniums and water molecules jointly construct host lattices while tetraalkylammonium cations are accommodated as guest species. Both two compounds formed sandwich-like hydrogen-bond inclusion compounds. In compound 1, the dimers composed of 2,4,6-pyridine-tricarboxylic anions and guanidiniums form 2D hydrogen-bonded layers by connecting with water molecules. In compound 2, 2,4,6-pyridine-tricarboxylic anions, guanidiniums and water molecules contribute to generate an undulate rosette hydrogen-bonded architecture. Interestingly, in compound 2, there are two species of guest molecules, tetraethylammonium and tetrapropylammonium, which are alternately arranged between the neighboring layers. Mixed guest cations accommodated in hydrogen-bonded inclusion compounds are seldom seen.  相似文献   

4.
N2H6CrF5H2O has been isolated for the first time from the system CrF3?N2H4?HF?H2O. We have investigated this compound and the already known (N2H5)3CrF6, by thermal analysis and IR spectroscopy. We have proved that the thermal decomposition of (N2H5)3CrF6 is accompanied by the disproportionation of hydrazinium(1+) ions. This was not the case with N2H6CrF5H2O. The final product of the thermal decomposition was impure CrF3 for either compound. We have analysed the IR spectrum of (N2H5)3CrF6 with reference to the known structure. The number of observed bands was smaller than required by the site symmetry. IR spectra suggested a strong deformation of the octahedron for N2H6CrF5H2O.Trans-configuration was assigned to the hydrazinium(2+) ion.  相似文献   

5.
Novel cocrystals of promethazine hydrochloride [PTZ‐Cl; systematic name: N,N‐dimethyl‐1‐(10H‐phenothiazin‐10‐yl)propan‐2‐aminium chloride] with succinic acid (PTZ‐Cl‐succinic, C17H21N2S+·Cl?·0.5C4H6O4), fumaric acid (PTZ‐Cl‐fumaric, C17H21N2S+·Cl?·0.5C4H4O4) and adipic acid (PTZ‐Cl‐adipic, C17H21N2S+·Cl?·0.5C6H10O4) were prepared by solvent drop grinding and slow evaporation from acetonitrile solution, along with two oxalic acid cocrystals which were prepared in tetrahydrofuran (the oxalic acid hemisolvate, PTZ‐Cl‐oxalic, C17H21N2S+·Cl?·0.5C2H2O4) and nitromethane (the hydrogen oxalate salt, PTZ‐oxalic, C17H21N2S+·C2HO4?). The crystal structures obtained by crystallization from tetrahydrofuran and acetonitrile include the Cl? ion in the lattice structures, while the Cl? ion is missing from the crystal structure obtained by crystallization from nitromethane (PTZ‐oxalic). In order to explain the formation of the two types of supramolecular configurations with oxalic acid, the intermolecular interaction energies were calculated in the presence of the two solvents and the equilibrium configurations were determined using density functional theory (DFT). The cocrystals were studied by X‐ray diffraction, IR spectroscopy and differential scanning calorimetry. Additionally, a stability test under special conditions and water solubility were also investigated. PTZ‐Cl‐succinic, PTZ‐Cl‐fumaric and PTZ‐Cl‐adipic crystallized having similar lattice parameter values, and showed a 2:1 PTZ‐Cl to dicarboxylic acid stoichiometry. PTZ‐Cl‐oxalic crystallized in a 2:1 stoichiometric ratio, while the structure lacking the Cl atom belongs has a 1:1 stoichiometry. All the obtained crystals exhibit hydrogen bonds of the type PTZ…Cl…(dicarboxylic acid)…Cl…PTZ, except for PTZ‐oxalic, which forms bifurcated bonds between the hydrogen oxalate and promethazinium ions, along with an infinite hydrogen‐bonded chain between the hydrogen oxalate anions.  相似文献   

6.
Four organic salts, namely benzamidinidium orotate (2,6‐dioxo‐1,2,3,6‐tetrahydropyrimidine‐4‐carboxylate) hemihydrate, C7H9N2+·C5H3N2O4·0.5H2O (BenzamH+·Or), (I), benzamidinium isoorotate (2,4‐dioxo‐1,2,3,4‐tetrahydropyrimidine‐5‐carboxylate) trihydrate, C7H9N2+·C5H3N2O4·3H2O (BenzamH+·Isor), (II), benzamidinium diliturate (5‐nitro‐2,6‐dioxo‐1,2,3,6‐tetrahydropyrimidin‐4‐olate) dihydrate, C7H9N2+·C4H2N3O5·2H2O (BenzamH+·Dil), (III), and benzamidinium 5‐nitrouracilate (5‐nitro‐2,4‐dioxo‐1,2,3,4‐tetrahydropyrimidin‐1‐ide), C7H9N2+·C4H2N3O4 (BenzamH+·Nit), (IV), have been synthesized by a reaction between benzamidine (benzenecarboximidamide or Benzam) and the appropriate carboxylic acid. Proton transfer occurs to the benzamidine imino N atom. In all four acid–base adducts, the asymmetric unit consists of one tautomeric aminooxo anion (Or, Isor, Dil and Nit) and one monoprotonated benzamidinium cation (BenzamH+), plus one‐half (which lies across a twofold axis), three and two solvent water molecules in (I), (II) and (III), respectively. Due to the presence of protonated benzamidine, these acid–base complexes form supramolecular synthons characterized by N+—H...O and N+—H...N (±)‐charge‐assisted hydrogen bonds (CAHB).  相似文献   

7.
Fragmentation patterns of 5-methylsulfanyl-1-vinyl-1H-pyrrol-2-amines under electron impact (70 eV) and chemical ionization (methane as reactant gas) were studied for the first time. The electron impact mass spectra of all the examined compounds contained a strong peak of molecular ion which decomposed along four pathways. Two pathways involved cleavage of the C-S bonds with elimination of methyl (major) and MeS radicals (minor), and the two others, decomposition of the pyrrole ring. The chemical ionization mass spectra displayed strong molecular, [M + H]+, and odd-electron [M + H ? SMe]+ ion peaks. N,N-Dimethyl-5-methylsulfanyl-4-phenyl-1-vinyl-1H-pyrrol-2-amine under chemical ionization with methane as reactant gas characteristically decomposed with formation of [M ? C4H9N]+ as the only fragment ion.  相似文献   

8.
The mass spectra of 5,6,6a,7,12,12a-hexahydrobenzo[a]anthracene and 2-methoxy, 3-methoxy-, 4-methoxy and 1-methyl-4-methoxy derivatives are reported. Among the fragment ions observed under electron impact ionization, [C8H8] and [M? C8H8] can be generated by a retro-Diels-Alder process. Studies of metastable ion reactions show these ions to be formed by fragmentation directly from the molecular ion. The CA spectra of the [C8H8] ions from the subject compounds were compared with spectra from ions of the same composition from various sources. From these data, kinetic energy release measurements and stereochemical considerations, it is concluded that these ions are formed by a stepwise, rather than a concerted mechanism.  相似文献   

9.
4-Amino-1,2,4-triazolium hexafluoridoniobate(V) and hexafluoridotantalate(V) (C2H5N4)MF6 (M = Nb, Ta) crystallizing in the monoclinic system (space group P21/n) are synthesized for the first time and their crystal structures and spectroscopic features are studied by single crystal X-ray diffraction and 1H and 19F NMR spectroscopy. The crystal structures of isostructural (C2H5N4)MF6 compounds are formed of octahedral complex [MF6] anions (M = Nb, Ta) and monoprotonated heterocyclic 4-amino-1,2,4-triazolium cations (C2H5N4)+ organized in a three-dimensional structure via N–H···F and N–H···N hydrogen bonds. The character and types of ion motions in the fluoride sublattice of (C2H5N4)MF6 are determined in a wide temperature range.  相似文献   

10.
The mass spectra of 1,2-diphenyl-pyrazolidine-3,5-dione and twenty-one 4-substituted derivatives are reported. Their fragmentation patterns have been studied by deuterium labelling, exact mass measurements, metastable studies by the defocusing technique and low energy spectra. Hydrogen rearrangements from the 4-position of the heterocycle and/or from the ß-position of the 4-substituent groups, lead to the main primary fragment ions [C12H11N2]+ (m/e 183) as shown by the metastables. The 4,4-d2 derivative shows an appreciable isotope effect even for molecular ions decomposing in the ion source. By comparison with the metastable abundances of competitive reactions, the molecular ions (m/e 252) of the 4-unsubstituted compound appear to be structurally different from the corresponding m/e 252 fragment ions formed from 4-derivatives by the loss of 4-substituent with H rearrangement. If only vinylic or aromatic hydrogen atoms are present, primary cleavage of the heterocyclic ring occurs with loss of OH·, C3O2 and C3HO2. Important rearrangements leading to elimination of C6H6N and C6H7N are typical for unsaturated substituents on position four having allylic hydrogen atoms. Fragment ions, identical to molecular ions of some compounds discussed here, are obtained by electron-impact and/or thermal decompostion of some complex compounds containing more than one 1,2-diphenyl-pyrazolidine-3,5-dione system. The [C6H5N2]+ (m/e 105) and [C6H5]+ (m/e 77) ions are common fragments of all the title compounds. Any hydrogen scrambling reactions between phenyl and heterocycle or 4-substituent groups can be excluded.  相似文献   

11.
The crystal structures of quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate trihydrate, C9H8N+·C7H5O6S·3H2O, (I), 8‐hydroxy­quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate monohydrate, C9H8NO+·C7H5O6S·H2O, (II), 8‐amino­quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate dihydrate, C9H9N2+·C7H5O6S·2H2O, (III), and 2‐carboxy­quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate quinolinium‐2‐carboxylate, C10H8NO2+·C7H5O6S·C10H7NO2, (IV), four proton‐transfer compounds of 5‐sulfosalicylic acid with bicyclic heteroaromatic Lewis bases, reveal in each the presence of variously hydrogen‐bonded polymers. In only one of these compounds, viz. (II), is the protonated quinolinium group involved in a direct primary N+—H⋯O(sulfonate) hydrogen‐bonding interaction, while in the other hydrates, viz. (I) and (III), the water mol­ecules participate in the primary intermediate interaction. The quinaldic acid (quinoline‐2‐carboxylic acid) adduct, (IV), exhibits cation–cation and anion–adduct hydrogen bonding but no direct formal heteromolecular interaction other than a number of weak cation–anion and cation–adduct π–π stacking associations. In all other compounds, secondary interactions give rise to network polymer structures.  相似文献   

12.
5‐Sulfosalicylic acid (5‐SSA) and 3‐aminopyridine (3‐APy) crystallize in the same solvent system, resulting in two kinds of 1:1 proton‐transfer organic adduct, namely 3‐aminopyridinium 3‐carboxy‐4‐hydroxybenzenesulfonate monohydrate, C5H7N2+·C7H5O6S·H2O or 3‐APy·5‐SSA·H2O, (I), and the anhydrous adduct, C5H7N2+·C7H5O6S or 3‐APy·5‐SSA, (II). Both compounds have extensively hydrogen‐bonded three‐dimensional layered polymer structures, with interlayer homo‐ and heterogeneous π–π interactions in (I) and (II), respectively.  相似文献   

13.
The title compounds are proton‐transfer compounds of cytosine with nicotinic acid [systematic name: 4‐amino‐2‐oxo‐2,3‐dihydropyrimidin‐1‐ium nicotinate monohydrate (cytosinium nicotinate hydrate), C4H6N3O+·C6H4NO2·H2O, (I)] and isonicotinic acid [systematic name: 4‐amino‐2‐oxo‐2,3‐dihydropyrimidin‐1‐ium isonicotinate–4‐aminopyrimidin‐2(1H)‐one–water (1/1/2) (cytosinium isonicotinate cytosine dihydrate), C4H6N3O+·C6H4NO2·C4H5N3O·2H2O, (II)]. In (I), the cation and anion are interlinked by N—H...O hydrogen bonding to form a one‐dimensional tape. These tapes are linked through water molecules to form discrete double sheets. In (II), the cytosinium–cytosine base pairs are connected by triple hydrogen bonds, leading to one‐dimensional polymeric ribbons. These ribbons are further interconnected via nicotinate–water and water–water hydrogen bonding, resulting in an overall three‐dimensional network.  相似文献   

14.
Mass spectra of the three isomeric vinylimidazoles have been compared and the structures of the fragment ions [C3H4N2] and [C5H5N2]+ have been investigated by collisionally activated dissociation mass spectrometry. The greater part of the non-decomposing ions m/z 68 from 2-vinylimidazole and from 2-imidazolecarboxylic acid methyl ester, and a minor part of this ion formed from the free acid, all have the same structure: the imidazole ring system, with hydrogens at both nitrogen atoms but none at C(2). An analogous structure, with an ethyl group at C(2), is proposed for the m/z 93 ion from 2-vinylimidazole.  相似文献   

15.
Pulse radiolysis of acetonitrile solutions of tetra-n-butyl ammonium salts of 2- and 4-carboxybenzophenones [BP-COO···N+(C4H9)4] were performed in order to generate directly the reduced forms of the benzophenone moieties within pre-formed ion pairs. In earlier studies on photochemical electron transfer reactions, ion pairs containing a tetraalkyl ammonium cation and a benzophenone radical anion were formed in an electron transfer to the triplet BP from a quencher consisting of a tetraalkyl ammonium salt of (phenylthio)acetic acid. In the current work, the [BP•−COO···N+(C4H9)4] ion pairs were formed by direct reduction of the salts without the complication of a third moiety, i.e., the (phenylthio)acetic anion. The spectra and kinetic parameters of the radiolytically-reduced salts were compared to the behavior of reduced forms of the 2- and 4-COOH substituted benzophenones. The results from the pulse radiolysis and photochemistry were compared and explained in terms of the different structures of the ion pairs.  相似文献   

16.
(N2H5)2GeF6 and (N2H6)2(GeF6)F2 have been prepared by reactions of N2H4·H2O and N2H6F2 with fluorogermanic acid. The solids have been characterized by chemical analysis and vibrational spectra. X-ray diffraction study has shown that crystals of (N2H5)2GeF6 are monoclinic, space group P 21/n, with unit-cell dimensions a = 6.015 (2), b = 5.249 (1), c = 11.181 (2) Å, β = 100.15 (2)o, and Z = 2. There are N2H5+ cations and GeF62? anions in the crystals interconnected by hydrogen bonds of the type NH····F and NH····N.  相似文献   

17.
Maleic acid and fumaric acid, the Z and E isomers of butenedioic acid, form 1:1 adducts with 2‐amino‐1,3‐thiazole, namely 2‐amino‐1,3‐thiazolium hydrogen maleate (2ATHM), C3H5N2S+·C4H3O4, and 2‐amino‐1,3‐thiazolium hydrogen fumarate (2ATHF), C3H5N2S+·C4H3O4, respectively. In both compounds, protonation of the ring N atom of the 2‐amino‐1,3‐thiazole and deprotonation of one of the carboxyl groups are observed. The asymmetric unit of 2ATHF contains three independent ion pairs. The hydrogen maleate ion of 2ATHM shows a short intramolecular O—H...O hydrogen bond with an O...O distance of 2.4663 (19) Å. An extensive hydrogen‐bonded network is observed in both compounds, involving N—H...O and O—H...O hydrogen bonds. 2ATHM forms two‐dimensional sheets parallel to the ab plane, extending as independent parallel sheets along the c axis, whereas 2ATHF forms two‐dimensional zigzag layers parallel to the bc plane, extending as independent parallel layers along the a axis.  相似文献   

18.
Two new dinuclear macrocyclic complexes, [Ni2L1(OAc)]·ClO4 (1) and [Co2L2(OAc)]·1.5(ClO4)·0.5Na·2(CH3OH) (2) (where H2L1 and H2L2 are the condensation products of N,N-bis(3-aminopropyl)-4-methoxybenzylamine with 2,6-diformyl-4-brominephenol and 2,6-diformyl-4-methylphenol in the presence of metal ions, respectively) have been synthesized and characterized by infrared spectra, elemental analysis, electrospray mass spectra, and X-ray single crystal diffraction. The interactions of the complexes with CT-DNA have been measured by UV-absorption titrations and fluorescence quenching experiments.  相似文献   

19.
The crystal structures of two dyestuffs, Na+·C11H8N3O2?·H2O, (I), and NH4+·C10H5N2O5?, (II), were determined from X‐ray powder diffraction data. In both structures, translationally related anions form stacks, and cations fill interstack channels. A comparison of the diffuse reflectance spectra of crystalline (I) and (II) with the absorption spectra of their aqueous solutions demonstrates that the geometry of their anions does not change significantly upon transfer from the crystalline to the solution state.  相似文献   

20.
Metastable ion peak shapes, dimensions and relative abundances have been measured for the three fragmentations [C3H6]+· → [C3H4]+· + H2, [C3H6]+· → [C3H5]+ + H· and [C3H6]+· → [C3H3]+ + H2 + H·. [C3H6]+· ions were derived from propene, cyclopropane, tetrahydrofuran, cyclohexanone, 2-methyl but-1-ene and cis-pent-2-ene. Activation energies for these fragmentations have been evaluated. Three daughter ion dissociations ([C3H5]+ → [C3H3]+ + H2, [C3H5]+ → [C3H4]+· + H· and [C3H4]+· → [C3H3]+ + H·) have been similarly examined. Ion structures have been determined and the metastable energy releases have been correlated with the thermochemical data. It is concluded that the molecular ions of propene and cyclopropane become structurally indistinguishable prior to fragmentation and that differences in their metastable ion characteristics can be ascribed wholly to internal energy differences; the latter can be correlated with the photoelectron spectra of the isomers. The pathway for the consecutive fragmentation which generates the metastable ion peak (m/e 42 → m/e.39) has been shown to be It is likewise concluded that fragmentating [C3H6]+· ions generated from the various precursor molecules are also structurally indistinguishable and cannot be classified with either molecular ion of the isomeric C3H6 hydrocarbons.  相似文献   

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