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1.
Base-catalysed hydrolysis of 2-formyl-3-methyl-1-phenyl-sulphonylindole results in the formation of 3-alkoxy-methyl-2-formylindoles. Cleavage of the 1-phenyl-sulphonyl group with sodium amalgam produces 2-hydroxymethyl-3-methylindole.  相似文献   

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The reciprocal system 3Tl2S + Bi2Se3 ? 3Tl2Se + Bi2S3 has been investigated by DTA, X-ray powder diffraction analysis, and emf measurements. Some polythermal sections and the isothermal section at 500 K of the phase diagram and the projection of the liquidus surface of this system have been constructed, and the types and coordinates of the invariant and univariant equilibria have been determined. The existence of wide regions of quaternary solid solutions based on the binary compounds Tl2S, Tl2Se, Bi2S3, and Bi2Se3, and solid solutions between the temary compounds TlBiS2 and TlBiSe2 have been established.  相似文献   

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RbLi2Ga2(BO3)3     
The structure of rubidium dilithium digallium tris­(borate), RbLi2Ga2(BO3)3, contains two‐dimensional sheets of open‐branched rings of GaO4 tetrahedra and planar BO3 triangles that are joined by LiO4 tetrahedra to form a three‐dimensional framework. Ten‐coordinate Rb atoms lie on twofold axes and occupy channels within the framework that extend along the b axis.  相似文献   

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Rate constants for the gas‐phase reactions of CH3OCH2CF3 (k1), CH3OCH3 (k2), CH3OCH2CH3 (k3), and CH3CH2OCH2CH3 (k4) with NO3 radicals were determined by means of a relative rate method at 298 K. NO3 radicals were prepared by thermal decomposition of N2O5 in a 700–750 Torr N2O5/NO2/NO3/air gas mixture in a 1‐m3 temperature‐controlled chamber. The measured rate constants at 298 K were k1 = (5.3 ± 0.9) × 10?18, k2 = (1.07 ± 0.10) × 10?16, k3 = (7.81 ± 0.36) × 10?16, and k4 = (2.80 ± 0.10) × 10?15 cm3 molecule?1 s?1. Potential energy surfaces for the NO3 radical reactions were computationally explored, and the rate constants of k1k5 were calculated according to the transition state theory. The calculated values of rate constants k1k4 were in reasonable agreement with the experimentally determined values. The calculated value of k5 was compared with the estimate (k5 < 5.3 × 10?21 cm3 molecule?1 s?1) derived from the correlation between the rate constants for reactions with NO3 radicals (k1k4) and the corresponding rate constants for reactions with OH radicals. We estimated the tropospheric lifetimes of CH3OCH2CF3 and CHF2CF2OCH2CF3 to be 240 and >2.4 × 105 years, respectively, with respect to reaction with NO3 radicals. The tropospheric lifetimes of these compounds are much shorter with respect to the OH reaction. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 490–497, 2009  相似文献   

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根据稀土离子能级的特点,对Ga2O3-La2O3-Yb2O3-Er2O3(HO2O3)体系的光谱性质进行了探讨,发现它们有二类发光性质:Stokes发光和反Stokes发光,研究了发光强度和发射波长与掺杂离子的依赖关系,观察到由能量的共振转移引起的荧光浓度猝灭现象,并取得了最大发光强度时的掺杂离子浓度和一些规律性结果.  相似文献   

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Crystals of PbCu3(OH)(NO3)(SeO3)3·1/2H2O [a=7.761(3)Å,b=9.478(4)Å,c=9.514(4)Å, =66.94(2)°, =69.83(2)°, =81.83(2)°, space group P ,Z=2] and Pb2Cu3O2(NO3)2(SeO3)2 [a=5.884(2)Å,b=12.186(3)Å,c=19.371(4)Å, space group Cmc21,Z=4] were synthesized under hydrothermal conditions. Their crystal structures were refined with three-dimensional X-ray data toR w=0.033 resp. 0.055. In PbCu3(OH)(NO3)(SeO3)3·1/2H2O the Cu atoms are [4+1] and [4+2] coordinated and via SeO3 groups a three-dimensional atomic arrangement is built up. In Pb2Cu3O2(NO3)2(SeO3)2 there are sheets, which are connected only via Pb-O bonds ranging from 2.98 Å to 3.16 Å.
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The influence of structural relationships between the components of (pseudo)binary systems with no intermediate compounds on the type of phase diagram was investigated. Structurally and chemically closely related Tl3SbS3 and Tl3AsS3 form a complete solid solution series whereas crystallographically different TlSbS2 and TlAsS2 constitute an eutectic type system.
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Preparation and Crystal Structure of the Dialkali Metal Trichalcogenides Rb2S3, Rb2Se3, Cs2S3, and Cs2Se3 Crystalline products were obtained by the reaction of the pure alkali metals with the chalcogens in the molar ratio 2:3 in liquid ammonia at pressures up to 3000 bar and temperatures around 600 K. The substances crystallize in the K2S3 type structure (space group Cmc21(NO. 36)). Unit cell constants see ?Inhaltsübersicht”?. The characteristic feature of this structure are bent polyanions X32?:(X = S,Se). The new described compounds are compared with the other known alkali metal trichalcogenides.  相似文献   

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Crystal Structure of Cs2PrO3 and also about Cs2CeO3, Cs2TbO3, Rb2CeO3, and Rb2TbO3 New prepared Cs2PrO3 (dark brown) is orthorhombic due to single crystal data, K2PbO3 type of structure (Cmc21) with a = 11.47, b = 7.722, c = 6.427 Å and Z = (4). Cs2CeO3 (colourless, a = 11.495, b = 7.753, c = 6.437 Å), Cs2TbO3 (red-brown, a = 11.37, b = 7.726, c = 6.142 Å), and the low-temperature form of (LT-) Rb2TbO3 (red-brown, a = 10.91, b = 7.390, c = 6.099 Å) are isotypic. Hitherto unknown HT-Rb2CeO3 (high-temperature form, colourless, a = 3.837, c = 18.47 Å, Z = 2, hexagonal) and “HT-Rb2TbO3” (red-brown, a = 3.773, c = 18.00 Å) correspond according to powder-data to the α-NaFeO2 type of structure. Cs2PrO3 has been measured magnetically (100–300 K). The Madelung Part of Lattice Energy (MAPLE) is calculated and discussed.  相似文献   

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The reaction of (CH3)2AsJ and AgN3 yields (CH3)2AsN3; a colourless liquid (b. p. 136°C) which dissolves as a monomeric in benzene. (CH3)2BiN3 is precipitated in form of colourless needles (dec. temp. 150°C) from an etherical solution of Bi(CH3)3 and HN3. According to its vibrational and mass spectra the molecules are not associated although the (CH3)2BiN3 is not soluble; dipole association of this polar molecules is assumed for the crystal structure. (CH3)2TlN3 can be obtained from TI(CH3)3 and ClN3 as well as from (CH3)2TlOH and HN3 in form of colourless needles and leaves (dec. temp. 245°C). According to its vibrational spectra it has an ionic structure, (CH3? Tl? CH3)+N?3.  相似文献   

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(CF3)2PAsH2 and (CF3)2AsAsH2 (CF3)2PAsH2 is obtained in yields between 30 and 60% according to eq. (1) (CF3)2AsAsH2 is formed by the analogous reaction with (CF3)2AsI, but is not sufficiently stable to be isolated. Both compounds are decomposed according to eq. (2) (CF3)2PAsH2 can be studied in solution below ?40°C; it is characterized by molar mass determination and by its n.m.r. spectra (1H, 19F, 31P). Reactions with polar [HBr, (CH3)2AsH, (CH3)2PN(CH3)2] and nonpolar [Br2, As2(CH3)4] reagents proceed by cleavage of the P? As bond.  相似文献   

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