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1.
Heterodiamantanes and Structurally Related Compounds. Part III. The Pentacyclic C11-Diethers 5, 13-Dioxapentacyclo [6.5.0.02,6.03,12.04,9]tridecane, 4, 13-Dioxapentacyclo [6.4.1.02,7.03,10.05,9]tridecane, and 3, 10-Dioxapentacyclo [7.3.1.02,7.04,12.06,11]tridecane In connection with the studies on heterodiamantanes and structurally related compounds the three novel pentacyclic diethers 3 – 5 were prepared starting from the cyclopentadienone dimer 6 . All four compounds have as common features a central carbocyclic 6-membered ring with four axial alkyl substituents and two oxygen functions in 1, 4 position. The required eleventh C-atom was introduced by dichlorocarbene addition either to 6 ( → 7 ) (Scheme 2) or to 29 ( → 28 ) (Scheme 4). Diether 3 was obtained by reduction of 26 (Scheme 2), a suitable precursor prepared either by intramolecular addition ( 24 → 26 ; Scheme 2) or substitution ( 30 → 26 , 31 → 26 ; Scheme 4), as well as by direct substitution ( 44 → 3 , 42 → 3 ; Scheme 5). Diether 4 was the product of a direct substitution ( 39 → 4 , 36 → 4 ; Scheme 5). The synthesis of diether 5 was achieved from the addition product 51 (resulting from the alcohols 47 and 48 ; Scheme 6). Diether 4 is the thermodynamically least stable of the three diethers 3 – 5 . It was easily isomerized to 5 on treatment with concentrated sulfuric acid in benzene whereas 3 and 5 remained unchanged under these conditions. 相似文献
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Thiosili‐Thiosilicates of the Rare‐Earth Elements: I. The Isotypic Compounds KCe[SiS4] and Eu2[SiS4] Both isotypic thiosilicates KCe[SiS4] (a = 649.15(6), b = 656.18(6), c = 863.96(8) pm, β = 107.531(9)°) and Eu2[SiS4] (a = 651.71(6), b = 659.54(6), c = 821.93(8) pm, β = 108.437(9)°) crystallize monoclinically in the space group P21/m and Z = 2. By the reaction of KCl, Ce2S3 and SiS2 in the ratio 1 : 1 : 1 using a sixfold molar amount of KCl as flux in evacuated silica tubes (7 d, 850°C) brownish yellow, plate‐shaped single crystals, resistant both to air and water are obtained. The conversion of Eu, S and SiS2 in molar ratios of 2 : 2 : 1 with an excess of CsCl as flux in evacuated silica tubes (7 d, 850°C) leads to deep red, plate‐shaped single crystals, which remain air‐ and water‐stable for a few days. The crystal structure contains isolated ortho‐thiosilicate units, that together with the Ce3+ or (Eu2)2+ cations build corrugated anionic layers parallel (001) according to {(Ce[SiS4])—} and {(Eu2[SiS4])2—}, respectively. These layers are alternatingly piled with cationic layers consisting solely of K+ or (Eu1)2+ cations. The latter show coordination numbers of eight in the shape of a bicapped trigonal prism, whereas the cations of the position Ce3+ and (Eu2)2+ have a (2+1)‐fold capped trigonal prismatic environment with a coordination number of 8+1. The comparison of both compounds KCe[SiS4] and Eu2[SiS4] (≡ EuEu[SiS4]) demonstrates, that Eu2+ is able to substitute both K+ and Ce3+ isomorphically. 相似文献
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H. Arm 《Helvetica chimica acta》1970,53(3):465-473
Activities and mixing functions of the following binary systems at 25° C are discussed: 1. mixtures of tetrahydrofuran with water, methanol, and cyclohexane; 2. mixtures of diethyl ether with water, methanol, and cyclohexane, and 3. mixtures of tetrahydrofuran with diethyl ether. Comparison with similar systems shows that in systems containing methanol, the strongest interactions are formation and breaking of hydrogen bonds between alcohol molecules; interactions between methanol and ether molecules play a minor rǒle. Systems containing water exhibit two main kinds of interaction: formation and breaking of hydrogen bonds between water molecules, and formation of hydrogen bonds between water and ether molecules. Deviations from ideality are larger for diethyl ether than for tetrahydrofuran in water and methanol, and smaller in cyclohexane. 相似文献
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Zusammenfassung Optisch aktives Ferroceno[b]indenon (2) wurde durch kinetische Racematspaltung des gut zugänglichenendo-Ferroceno-indenols3 mit (+)--Phenylbuttersäure-anhydrid in optischen Ausbeuten um 20% erhalten. Aus den Ergebnissen dieser Racematspaltung (auch für dasexo-Carbinol5) ließen sich auf Grund der bekannten Absolutkonfiguration (+)-(1R)-2 die relativen stereochemischen Größen von Ferrocen und Benzol (Fc>Phenyl) erstmals festlegen.Mehrere Folgeprodukte von (+)-2 (darunter Ferrocenohydrindene) wurden dargestellt und ihre chiroptischen Eigenschaften mit jenen von strukturell verwandten Ferrocenderivaten (wie13–18) verglichen (und diskutiert). DieCD-Kurven wurden einer Bandenanalyse unterworfen.
Mit 6 Abbildungen
Herrn Prof. Dr.M. Pailer in herzlicher Verbundenheit zum 60. Geburtstag gewidmet.
32. Mitt. (3. Mitt. über optisch aktive Aryl-ferrocene, 53. Mitt. über Ferrocenderivate):H. Falk, H. Lehner undK. Schlögl, Mh. Chem.101, 967 (1970). 相似文献
Stereochemistry of metallocenes, XXXIII. (ferrocenes, LIV). Optically active arylferrocenes, IV: Optically active ferroceno[b]indenes, hydrindenes, and related compounds
Optically active ferroceno[b]indenon (2) was obtained by kinetic resolution of the easily accessibleendo ferroceno indenol (3) with (+)--phenylbutyric anhydride with optical yields of 20%. From the results of this resolution (also for theexo-carbinol5) on the basis of the known absolute configuration (+)-(1R)-2 the relative stereochemical sizes of ferrocene and benzene could be established for the first time:Fc>phenyl.Several subsequent products of (+)-2 (amongst them ferroceno hydrindenes) were prepared and their chiroptical properties compared with those of structurally related ferrocenes (such as13–18) (and discussed). TheCD-curves were subjected to a band analysis.
Mit 6 Abbildungen
Herrn Prof. Dr.M. Pailer in herzlicher Verbundenheit zum 60. Geburtstag gewidmet.
32. Mitt. (3. Mitt. über optisch aktive Aryl-ferrocene, 53. Mitt. über Ferrocenderivate):H. Falk, H. Lehner undK. Schlögl, Mh. Chem.101, 967 (1970). 相似文献
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Compounds of L-Ascorbic Acid with Metals. II. Titanyl Ascorbates The titanyl ascorbates TiO(C6H7O6)2 · 2 H2O and TiO(OH)(C6H7O6) the preparation of which has been described elsewhere are characterized by electronic, infrared, and 1H-nmr spectra. From measurements of the H3O+ concentration of aqueous solutions of both compounds a simple model for describing their protolytic behaviour is derived. 相似文献
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Ulrich Müller 《无机化学与普通化学杂志》1998,624(3):529-532
Structural Relations among Trigonal Compounds with Hexagona Closest-packing of Anions and Occupied Octahedral Voids. Calculation of the Numbers of Possible Structure Types, 2nd Communication [1] The unit cell of the hexagonal closest-packing is enlarged trifold and trigonal symmetry is retained. When part of the octahedral voids are then occupied, several known crystal structure types result. The crystallographic group-subgroup relations are shown. For each of the space groups the number of possible independent structure types is calculated according to chemical composition. Known representatives include RhF3, corundum, ilmenite, LiNbO3, BiI3, WCl6, LiSbF6, Na3GdCl6, and Li2ZrF6; distorted varieties are RuBr3, PI3 and N(CH3)3. No representative is known for one possible structure type for compounds MX3 in the space group R32; it could be adopted by WCl3 and contains pairs of face-sharing octahedra linked by common vertices. 相似文献
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Formation of Organosilicon Compounds. LX. Crystal and Molecular Structure of Heptamethyl-tetrasila-[2,2,2]-barrelan Si4C11H28 1,1,3,5,5,7,7-Heptamethyl-1,3,5,7-tetrasila-[2,2,2]-barrelan Si4C11H28 crystallizes in the orthorhombic space group Pn21a with a = 12.293, b = 9.903, c = 14.018 Å and Z = 4 formula units. The six-membered rings have the skew-boat conformation with a torsion angle of 23.5° with respect to the molecular axis. The skew-boat conformation results from the interaction of CH3- and CH2- groups. The mean value for the bond length is Si? C = 1.881 Å. The distances Si? CH2 = 1.873 Å are somewhat smaller than the others (1.887 Å). 相似文献
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Hydroxo Compounds. 10. The Sodium Oxohydroxostannates(II) Na4[Sn4O(OH)10] and Na2[Sn2O(OH)4] Na4[Sn4O(OH)10] = Na4[Sn(OH)3]2[Sn2O(OH)4] ( I ) and Na2[Sn2O(OH)4] ( II ) have now been doubtlessly characterized as the first Na-hydroxostannates(II). I crystallizes monoclinic in P21/n (a = 1522.4(5) pm, b = 830.0(2) pm, c = 1276.0(3) pm, β = 104.8(2)°, Z = 4, R = 0.047, 1137 Ihkl); II crystallizes orthorhombic in P212121 (a = 1450(2) pm, b = 1665(2) pm, c = 590.7(8) pm, Z = 8, R = 0.042, 1208 Ihkl). II is identical with the compound which was described up to now as “Na[Sn(OH)3]”. The new compounds contain the complex anions [Sn(OH)3]? and [Sn2O(OH)4]2?, whose structures are now proved. The oxotetrahydroxo-distannate(II) anion [Sn2O(OH)4]2? exhibits a syn-conformation with respect to the projection along the (Sn? Sn) vector. The two compounds crystallize with pronounced layer structures, which show direct topotactical relations with one another as well as with SnO. This relates closely to the fast formation of SnO from crystals of I and II . 相似文献
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Organometallic Compounds of the Lanthanides. 155 [1] Synthesis and Characterization of New Lanthanocene Complexes containing Silylated Cyclopentadienyl Ligands The trichlorides of yttrium, samarium, and lutetium react with two equiv. of K[C5H4SiEt3] ( 1 ) to form the dimeric compounds [(η5‐C5H4SiEt3)2LnCl]2 (Ln = Y ( 2 ), Sm ( 3 ), Lu ( 4 )). These react with one equiv. of methyllithium to give the corresponding dimeric lanthanocenemethyl complexes [(η5‐C5H4SiEt3)2LnMe]2 (Ln = Y ( 5 ), Sm ( 6 ), Lu ( 7 )). The reaction between samarium trichloride and lutetium trichloride, respectively with two equiv. of K[1, 3‐C5H3(SiMe3)2] followed by one equiv. of methyllithium results in the formation of the monomeric methyl complexes [η5‐1, 3‐C5H3(SiMe3)2]2LnMe(THF) (Ln = Sm ( 8 ), Lu ( 9 )). The new compounds have been characterized by elemental analysis, mass spectrometry, 1H‐ and 13C{1H} NMR spectroscopy, as well as 1 — 7 by single crystal X‐ray structure analysis. 相似文献
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Herbert Schumann Jrn Winterfeld Markus R. Keitsch Katja Herrmann Jrg Demtschuk 《无机化学与普通化学杂志》1996,622(9):1457-1461
Organometallic Compounds of the Lanthanoids. 111. Synthesis and Characterization of Cationic Metallocene Complexes of the Lanthanoides. X-Ray Crystal Structure of [Cp Yb(THF)2][BPh4] Cationic organolanthanoide compounds [(C5H4R)2Sm(THF)2][BPh4] (R = tBu ( 1 ), SiMe3 ( 2 )), [PyrSm(THF)][BPh4] ( 3 ) (Pyr* = NC4H2tBu2-2,5), [CpLn(THF)2][BPh4] (Cp* = C5Me5; Ln = Y ( 4 ), Yb ( 5 )), and [(C5Me4Et)2 Ln(THF)2][BPh4] (Ln = Y ( 6 ), Sm ( 7 )) have been synthesized by oxidation of the divalent metallocenes [(C5H4R)2Sm(THF)2] (R = tBu, SiMe3), [PyrSm(THF)], [CpYb(THF), and [(C5Me4Et)2Sm(THF)] with Ag[BPh4] and by protolysis of the lanthanoide alkyls [CpYMe(THF)], [CpYbCH(SiMe3)2], and [(C5Me4Et)2LnCH(SiMe3)2] (Ln = Y, Sm) by [NEt3H][BPh4]. The 1H- and 13C-NMR spectra of the new compounds are discussed. 5 crystallizes in the space group P21/c with a = 10.604(7), b = 21.749(3), c = 19.124(4) Å, β = 96.47(4)°, Z = 4 and V = 4383(3) Å3 (R = 0.0291 for 8517 observed reflections with Fo ≥ 4σ (Fo). 相似文献
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RAMAN and IR Spectroscopic Investigation on Alkyl Derivatives of Arsenic-Acid. V. Vibrational Spectra of Dimethyl and Diethyl Arsinic Acid and their Reaction Products with HCl The RAMAN and IR spectra of (CH3)2AsO2H–partially deuterated–and (C2H5)2AsO2H and of the reaction products of these acids with HCl (solid and in concentrated aqueous solution) are discussed. The symmetry of the R2AsO2H skeleton is Cs. of the [R2As(OH)2]+ ion very probably C2v. Whereas (CH3)2AsO2H gives with HCl only a compound (CH3)2ACO2H · HCl (connected by H bonds), the weaker (C2H5)2AsO2H is able to form a salt [(C2H5)2As(OH)2]Cl. The H bonds in the substances are discussed. 相似文献
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Es wird über Darstellung und Kristallstruktur ternärer AMnX-Verbindungen (A ? Li, Na; X ? P, As, Sb, Bi) berichtet. Sie kristallisieren tetragonal in Raumgruppe P4/nmm-D4h7, wobei sich LiMnX und NaMnX durch unterschiedliche Punktlagen der Alkaliatome unterscheiden. Die AMnX-Strukturen werden mit denen verwandter AMX-Verbindungen verglichen (A ? Li, Na, K, Rb; M ? Be, Mg, Zn, Cd; X ? 5b-Element). Ternary Compounds of Lithium and Sodium with Manganese and Elements of the Fifth Main Group Formation and crystal structure of ternary AMnX compounds (A ? Li, Na; X ? P, As, Sb, Bi) are reported. These compounds crystallize in the tetragonal space group P4/nmm-D. The structures of LiMnX and NaMnX differ by the positions of the alkali atoms. Structural relationship to AMX compounds (A ? Li, Na, K, Rb; M ? Be, Mg, Zn, Cd; X ? 5b element) are discussed. 相似文献
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Thiosilicates of the Rare‐Earth Elements: III. KLa[SiS4] and RbLa[SiS4] – A Structural Comparison Pale yellow, platelet shaped, air‐ and water resistant single crystals of KLa[SiS4] derived from the reaction of lanthanum (La) and sulfur (S) with silicon disulfide (SiS2) in a molar ratio of 2 : 3 : 1 with an excess of potassium chloride (KCl) as flux and source of potassium ions in evacuated silica ampoules at 850 °C within seven days. The analogous reaction utilizing a melt of rubidium chloride (RbCl) instead also leads to yellow comparable single crystals of RbLa[SiS4]. The potassium lanthanum thiosilicate crystallizes monoclinically with the space group P21/m (a = 653.34(6), b = 657.23(6), c = 867.02(8) pm, β = 107.496(9)°) and two formula units per unit cell, while the rubidium lanthanum thiosilicate has to be assigned orthorhombically with the space group Pnma (a = 1728.4(2), b = 667.23(6), c = 652.89(6) pm) and four formula units in its unit cell. In both compounds the La3+ cations are surrounded by 8+1 sulfide anions in the shape of tricapped trigonal prisms. The Rb+ cations in RbLa[SiS4] show a coordination number of 9+2 relative to the S2? anions, which form pentacapped trigonal prisms about Rb+. This coordination number, however, is apparently too high for the K+ cations in KLa[SiS4], so that they only exhibit a bicapped trigonal prismatic environment built up by eight S2? anions. The isolated thiosilicate tetrahedra [SiS4]4? of the rubidium compound are surrounded by La3+ both edge‐ and face‐capping, but terminal as well as edge‐ and face‐spanning by Rb+. In the potassium compound there is no change for the La3+ environment about the [SiS4]4? tetrahedra, but the K+ cations are only able to attach terminal and via edges. The whole structure is built up by anionic equation/tex2gif-stack-1.gif{La[SiS4]}? layers that are separated by the alkali metal cations. In direct comparison the two thiosilicate structures can be regarded as stacking variants. 相似文献