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The crystal structure and crystallochemical features of a Fe-deficient zirconium-rich analog of eudialyte from the Lovozero alkaline massif (Kola peninsula) have been investigated. The unit-cell parameters of the mineral are found to be a = 14.198(1) Å, c = 30.380(1) Å, and V = 5303.9(1) Å3; sp. gr. R3m. The crystal structure is refined to the final reliability factor R = 4.2% in the anisotropic approximation of atomic displacements using 3174 reflections with F > 3σ(F). The crystallochemical formula of the mineral (Z = 3) is [Na10.38(H3O,H2O)2.79Ce0.45Sr0.4K0.2][Ca3.9Mn1.2Fe0.9][VIINa VZr0.87]Zr3[Si1.48Ti0.31Nb0.21][Si24O72](OH)2.9 (H2O)1.26 (Cl, S)0.94 (Roman numerals are the coordination numbers (CNs) of cations at the M2 key site). The regularities of block isomorphism in the vicinity of the M2 site in the structure of the mineral under study and related eudialyte-group minerals are discussed. [ABSTRACT FROM AUTHOR]

Anion-radical salt of 7,7,8,8-tetracyanoquinodimethane with N-methyl-2,2'-dipyridyl cation is synthesized. Its composition is determined using electron spectroscopy and elemental analysis. The crystal and molecular structures of the salt are determined using X-ray diffraction (XRD) analysis. The salt contains homogeneous stacks of 7,7,8,8-tetracyanoquinodimethane particles, which is a necessary condition for high electrical conductivity. The IR spectrum of the salt exhibits specific features characteristic of organic metals: continuous absorption (electron continuum) and manifestation of electron–phonon interaction. These characteristics of the salt give grounds to assign it to organic metals. [ABSTRACT FROM AUTHOR]

The crystal structure of a potentially new mineral, the Fe2+-dominant analogue of armalcolite with the idealized formula Fe2+Ti2O5 has been solved. The sample studied originates from a pneumatolytic association related to the lamproite complex of SE Spain. The mineral is orthorhombic, space group Cmcm, the unit-cell parameters are a = 3.7325(1) Å, b = 9.7649(4) Å, c = 9.9902(3) Å, V = 364.12(2) Å3. The crystal-chemical formula (Z = 4) is in good agreement with the chemical composition of the mineral. [ABSTRACT FROM AUTHOR]

The crystal structures of ion-exchange products of the zeolite-group mineral amicite from Khibiny Alkaline Massif with silver and rubidium salts have been studied. The investigated samples are monoclinic (sp. gr. P21 and I2/a); their crystallochemical formulas (Z = 1) are Ag8(Al8Si8O32) ⋅ 10.6H2O and K0.4Na0.7Rb6.9(Al8Si8O32) ⋅ 4.5H2O; the unit cell parameters are a = 9.272(2) and 10.043(2) Å, b = 9.997(2) and 9.748(2) Å, c = 10.380(3) and 10.265(2) Å, β = 90.821(8)° and 90.09(3)°, V = 962.0(4) and 1005.0(3) Å3, respectively. In the Ag-amicite structure, 22 partially occupied sites of the extra-framework components (Ag and H2O) are localized. In the Rb-amicite structure, most of rubidium atoms are located in two sites with the occupancies of 0.414(6) and 0.389(5). The cross-sectional areas of the zeolite channels are 3.5 × 4.5 and 2.3 × 6.3 Å2 for Ag-amicite and 3.0 × 4.3 and 3.0 × 3.9 Å2 for Rb-amicite. [ABSTRACT FROM AUTHOR]

Processes and products of ion exchange of günterblassite (K,Ca,Ba,Na)3–xFe1–y[(Si,Al)13O25(OH,O)4]·7H2O (microporous silicate, structurally intermediate between smectites and zeolites) and three samples of zeolite gmelinite (Na,K,Ca,Mg)x[(Si,Al)12O24)·nH2O of different composition with cations of various metals were studied. It was shown that günterblassite exhibits high activity and sorption capacity with respect to Rb+, Cs+, Ag+ cations and, to a lesser extent, Pb2+ and Ba2+: even at room temperature for 1 h, the concentration of M2O (M = Rb, Cs, Ag) in the sorbent reaches 10–13 wt %. The ion exchange in gmelinite occurs according to the frontal mechanism, propagating from the periphery of the crystal to its center. In reactions with Pb2+, the activity of gmelinite increases with a rise in its sodium content and decreases with a rise in potassium content. The crystal structure of Pb-substituted gmelinite was studied and it was shown that Pb2+ ions populate both zeolite channels. Synthetic gmelinite obtained from cheap natural raw materials and fly ash from thermal power plants can be used to purify water from lead. [ABSTRACT FROM AUTHOR]

The structure of the radical anion salt (RAS) of 7,7,8,8-tetracyanedimethane (TCNQ) with a cation based on 2-amin-5-chloro-pyridine (2-NH2-5-Cl–Py, Am), that is, (N–CH3-2-NH2-5-Cl–Py) (TCNQ) (CH3CN), (I) is presented. Unlike most TCNQ RASs, which contain flat TCNQ particle stacks, RAS I contains practically isolated (TCNQ) π-dimers with unusually short distances between the planes in the dimers: 3.24 Å. In the RAS I IR spectra special features are observed that correspond to the vibronic interactions of molecular vibrations. [ABSTRACT FROM AUTHOR]

The radical-cationic salts based on tetrathiafulvalene derivatives and bis(dicarbollide) transition metal complexes [3,3′-M(1,2-C2B9H11)2]− (M = Co, Ni, Fe, Cr) are promising for the creation of new molecular conductive materials due to the almost unlimited possibilities of their modification. The relationships between the properties of both components of the cation-radical salts, their crystal structure, and electrical and magnetic properties have been analyzed on the basis of the literature and our own data. The effect of various substituents in metallacarborane anions on the structure and physical properties of their radical cation salts based on tetrathiafulvalene and its derivatives has been revealed. Data on the structure and properties of the radical cation salts with other borate anions are presented for comparison. [ABSTRACT FROM AUTHOR]

ording to ? and ? NMR data, enamines of 3-formyl-4-hydroxycoumarin exist in the keto enamine tautomeric form and undergo Z/E-isomerization around the C=C bond in CDCl, DMSO-d, and CDOD at room temperature. The activation energies of ?/Z-isomerization were measured experimentally and calculated by the B3LYP/6-311++G(d,p) method. An X-ray diffraction study showed that 3-(benzyliminomethyl)chromane-2,4-dione in the crystalline state exists as a mixture of two keto enamine isomers. [ABSTRACT FROM AUTHOR]

The radical cation salts of tetrathiafulvalene (TTF) and bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) with iodo derivatives of cobalt bis(dicarbollide), (TTF)[9,9′,12,12′-I-3,3′-Co(1,2-CBH)] and (BEDT-TTF)[9,9′(12′)-I-3,3′-Co(1,2-CBH)], respectively, were synthesized and their crystal structures were determined. The introduction of iodine atoms into the lower rim of the dicarbollide ligands, unlike the substitution at the upper rim, leads to insignificant changes in the crystal structure and the conductivity of the radical cation salts compared to the analogous salts based on unsubstituted cobalt bis(dicarbollide). [ABSTRACT FROM AUTHOR]

Previously unknown bis[2-(4- tert-butyl)phen]ethylphosphine sulfide is obtained with a high yield from 4- tert-butyl styrene, red phosphorus, and elemental sulfur. Using single crystal XRD, multinuclear NMR, IR, and UV spectroscopy, it is found that the phosphorus atom is four-coordinated in the bis[2-(4- tert-butyl)phen]ethylphosphine sulfide molecule (regardless of the phase state of the compound: crystal, solution). By the example of phosphorylation of bis[2-(4- tert-butyl)phen]ethylphosphine sulfide acetylene in the KOH-DMSO system it is shown that the reaction proceeds by double addition with the participation of phosphorus-centered nucleophiles. [ABSTRACT FROM AUTHOR]

Steric structure of fluorinated 2-arylhydrazono-3-oxo esters was studied by 1H, 19F, and 13C NMR spectroscopy and X-ray analysis. It was found that these compounds in the crystalline state and in solutions in acetone- d6, DMSO- d6, and CDCl3 exist as Z isomers with the ester fragment involved in intramolecular hydrogen bond with the hydrazone NH proton. Exceptions are alkyl 2-arylhydrazono-4,4-difluoro-3-oxobutanoates which exist in acetone- d6 as mixtures of Z and E isomers, the former prevailing. Unlike fluorinated analogs, ethyl 2-(4-methylphenyl)hydrazono-3-oxobutanoate in crystal has the structure of E isomer in which intramolecular hydrogen bond is formed between the NH proton and acetyl carbonyl group. The same compound in acetone- d6, DMSO- d6, and CDCl3 gives rise to a mixture of Z and E isomers, the latter prevailing. [ABSTRACT FROM AUTHOR]

3-Phenylamino-5-phenylimino-1,2,4-dithiazole reacted with 1-acyl-2-phenylacetylenes in ethanol or toluene on heating (78–80°C, 1 h) in chemo- and regioselective fashion to give previously unknown N-[5-acyl-3,4-diphenyl-1,3-thiazol-2(3 H)-ylidene]- N′-phenylthioureas (yield 57–60%). The structure of N-[5-benzoyl-3,4-diphenyl-1,3-thiazol-2(3 H)-ylidene]- N′-phenylthiourea was proved by X-ray analysis. [ABSTRACT FROM AUTHOR]

Fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones react with methylamine in different ways, depending on the substrate structure. Arylhydrazones having a short fluoroalkyl substituent (RF = CF3, HCF2CF2) react at the carbonyl group adjacent to the nonfluorinated substituent to give 3-alkyl(aryl)-2-aryldiazenyl-3-methylamino-1-polyfluoroalkylprop-2-en-1-ones. Arylhydrazones with a long-chain fluoroalkyl group (RF = C3F7 and longer) and a bulky nonfluorinated group take up methylamine molecule at the carbonyl group linked to the fluorinated substituent, and the subsequent haloform reaction yields N-methyl-2-arylhydrazono-3-oxobutanamides. Both types of products are formed in reactions of methylamine with 1,2,3-triketone 2-arylhydrazones having a long fluoroalkyl group and methyl group at the other carbonyl group. Template condensation of fluoroalkyl-containing 1,2,3-trione 2-arylhydrazones with methylamine over Ni(II) template gives bis[3-alkyl(aryl)-1-polyfluoroalkyl-3-methylamino-2-aryldiazenylprop-2-en-1-onato- N,N′]-nickel(II), regardless of the size of the fluoroalkyl substituent. The same complexes and their copper analogs can be obtained by treatment of 3-alkyl(aryl)-2-aryldiazenyl-3-methylamino-1-polyfluoroalkylprop-2-en-1-ones with the corresponding metal salts. [ABSTRACT FROM AUTHOR]

Bis(2-phenylethyl)phosphine selenide was obtained with 86% yield from bis(2-phenylethyl)phosphine and selenium. XRD, IR, UV, and multinuclear NMR spectroscopic studies revealed that the phosphorus atom in the bis(2-phenylethyl)phosphine selenide molecule is four-coordinated irrespective of the phase state (crystals or solution). [ABSTRACT FROM AUTHOR]