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About the Na5[GaO4]-Relationship: KNa4[GaO4] and CsK4[GaO4] KNa4[GaO4] was newly prepared from binary oxides (powders) and also from KGaO2/Na2O/K2O (colourless columnar single crystals) in a closed Ag-cylinder at 600 and 650°C. Space group Pbca with a = 1046.1(2), b = 596.3(1), c = 1871.1(3) pm, Z = 8 [Four-circle-diffractometer data, 1138 I0(hkl), MoKα, R = 8.29, Rw = 6.76%, anisotropic refinement] (Parameter s. text). Colourless cubic single crystals of hitherto unknown CsK4[GaO4] are formed by reaction of K2O, CsGaO2, and Cs2O (surplus) in a closed Au-tube at 580°C. Space group Pbca with a = 1154.7, b = 667.7, c = 2096.6 pm, Z = 8 [Four-circle-diffractometer data, 1798 I0(hkl), MoKα, R = 7.62, Rw = 7.68%, anisotropic refinement] (Parameter s. text). Both crystal structures belong to the Na5[GaO4] type. Structural aspects, ECoN, and MAPLE of KNa4[GaO4] and CsK4[GaO4] in relation with Na5[GaO4] are discussed. 相似文献
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The condensations of 1-(2-hydroxyphenyl) pyrroles with a variety of carbonyl compounds are shown to give new 4-substituted-4H-4-methylpyrrolo[2,1-c][1,4]benzoxazines. Some of the products were further functionalized. The ir, uv, and pmr spectra of the title heterocyclic system are discussed. Reaction of 1-(2-hydroxyphenyl) pyrrole with dimethyl acetylenedicarboxylate yielded dimethyl 3-(2-hydroxyanilino) phthalale; a mechanistic rationale which accounts for the result involves a rearrangement of the hypothetical Diels-Alder adduct. 相似文献
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Thio- and Selenomercurates(II). K6[HgS4], K6[HgSe4], Rb6[HgS4] and Rb6[HgSe4] We prepared by annealing intimate mixture of pure samples of K2S, K2Se, Rb2S, and Rb2Se with HgS or HgSe [360–380°C, 7d, Duran-glass-seal with Argon] with hexagonal Na6ZnO4 isotypic new mercurates: K6[HgS4] [bright citronic yellow a = 9.985, c = 7.652 Å], K6[HgSe4] [light orange yellow a = 10.36, c = 7.883 Å], Rb6[HgS4] [bright yellow a = 10.34, c = 7.942 Å], Rb6[HgSe4] [orange-red a = 10.72, c = 8.192 Å]. The crystal structure of K6 Hgs4 is elucidated by using diffractometer data of single crystals: P63mc, C46v, it is R = 6.6% for 304 reflexes [h k o–h k 4, anisotropic refinement MoKα]; for position and parameters see text drö = 2.835, dpyk = 2.99 g · cm?3. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, are calculated and discussed. 相似文献
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Cs4[IrO4], a New Iridate with Planar Anion [IrO4]4? For the first time we obtained black single crystals of Cs4[IrO4] by heating intimate mixtures of CsO0.52 and IrO2 (molar ratio Cs : Ir = 4.30 : 1.00; “Ag-bomb”, 740°C/86 d). Cs4[IrO4] crystallizes monocline, C 2/m, with a = 1031.66(8) pm, b = 671.61(4) pm, c = 660.44(6) pm, b? = 108.118(7)° and Z = 2 in the K4[IrO4]-type. The structure has been determined by four-circle-diffractometer data (PW 1100 from Phillips, Ag? Kα , graphite) with 841 I0(hkl) with I ≥ 3s?(F) (from 947 I0(hkl) out of 3529 measured reflexes). The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, are calculated and discussed. 相似文献
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Azulene reacts with paraformaldehyde in the presence of florisil to give excellent yields of calix[4]azulene. 相似文献
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The review deals with the synthesis, chemical modification, and complexing properties of a new class of molecular receptors, porphyrin-calix[4]arene conjugates.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 807–826.Original Russian Text Copyright © 2005 by Mamardashvili, Koifman. 相似文献
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O. V. Surov E. V. Plevina M. I. Voronova V. V. Vinogradov N. Zh. Mamardashvili 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(5):783-788
Microporous material with a large surface area is obtained through the controlled desolvation of 4-tert-butylcalix[4]arene complex with acetonitrile. 相似文献
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V. L. Savel'ev O. L. Samsonova V. S. Troitskaya V. P. Lezina 《Chemistry of Heterocyclic Compounds》1991,27(1):108-112
4H-[1]benzopyrano[3,4-c][1,2,5]selenodiazol-4-one has been synthesized by the reaction of 3,4-diaminocoumarin with selenous acid and its reaction with several nucleophiles (alkali, ammonia, amines, hydrazine hydrate) and its nitration have been studied. Using PMR spectroscopy, a comparative kinetic study of the opening of the lactone ring in 6,8-dinitro-4H-[1]benzopyrano[3,4-c][1,2,5]seleno- and thiadiazol-4-ones has been carried out.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 128–133, January, 1991. 相似文献
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PPh4[As3S3Cl4] and PPh4[As3S3Br4] When As2S3 reacts with PPh4X and HX in 1,2-C2H4X2 (X = Cl, Br), the title compounds are obtained as minor products; the main products are PPh4[As2SX5]. Their crystal structures were determined by X-ray diffraction. PPh4[As3S3Cl4]: a = 1187.7, b = 1090.9, c = 1191.8 pm, α = 82.91, β = 88,93, γ = 88.52°; twins with twin plane (100); R = 0.109 for 1618 observed reflexions of one twin crystal. PPh4[As3S3Br4]: a = 1119.7, b = 1177.5, c = 1204.1 pm, α = 81.59, β = 85.88, γ = 88.25°; R = 0.061 for 2331 observed reflexions. Both compounds crystallize in the space group P1 , Z = 2, and can be considered to be isotypic. Nevertheless, PPh4[As3S3Br4] does not form twins as PPh4[As3S3Cl4]. The crystals consist of PPh4+ and [As3S3X4]? ions. In the anions, the three As atoms of an As3S3 ring in the chair conformation are commonly joined to an X atom and each As atom is bonded to one further terminal X atom. Cations and anions are packed in alternating layers. 相似文献
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Synchrotron radiation X-ray powder diffraction data (SPDD) have been obtained for Ag[AgF4]2, Au[AuF4]2, Ag[AuF4], and Ag[AuF6]. Ag[AgF4]2 and Au[AuF4]2 are isostructural with Ag[AuF4]2, space group (SG) P2(1)/n, Z = 2, with the following: for Ag[AgF4]2 a = 5.04664(8), b = 11.0542(2), c = 5.44914(9) A, beta = 97.170(2) degrees; for Au[AuF4]2 a = 5.203(2), b = 11.186(3), c = 5.531(2) A, beta = 90.55(2) degrees. The structure of Ag[AgF4]2 was refined successfully (SPDD) applying the Rietveld method, yielding the following interatomic distances (A): AgII-F = 2.056(12), 2.200(13), 2.558(13); AgIII-F = two at 1.846(12), others = 1.887(12), 1.909(13), 2.786-(12), 2.796(12), 2.855(12). AgAuF4, like other AA'F4 salts (A = Na-Rb; A' = Ag, Au), crystallizes in the KBrF4 structure type, SG I4/mcm (140), Z = 4 with a = 5.79109(6), c = 10.81676(7) A. SPDD gave (in A) four AuIII-F = 1.89(1) and eight AgI-F = 2.577(7). SPDD for AgAuF6 confirmed that it has the LiSbF6 structure, SG R3, Z = 3, with a = 5.2840(2), c = 15.0451(6) A. 相似文献
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Muriel Funck 《Tetrahedron letters》2010,51(49):6399-6402
A series of resorcin[4]arene and pyrogallol[4]arene macrocycles have been synthesized efficiently within 5 min, affording crystalline products suitable for single crystal X-ray diffraction, utilising microwave irradiation in a ‘one-pot’ reaction whilst controlling the selective formation of the rccc cone stereoisomer. 相似文献