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  • 1
    Electronic Resource
    Electronic Resource
    (β-Cyclodextrin)2·KI7·9 H2O. Spatial fitting of a polyiodide chain to a given matrix (1983)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 1 (1983), S. 181-191 
    Details
    ISSN: 1573-1111
    Keywords: (β-cyclodextrin)2·KI7·9H2O ; zigzag and linear polyiodide ; I2·I 3 − ·I2 ; starch-iodine model ; crystal structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract α-Cyclodextrin, a torus shaped molecule with a 5 Å wide central cavity, forms a number of deep green, blue and black crystals when complexed with iodine/metal iodide. In contrast, β-cyclodextrin, having a 6 Å cavity produces only one type of reddish-brown crystal, no matter what metal iodide is used. The complex (β-cyclodextrin)2 ·KI7·9H2O displays space groupP21 (pseudo-C2) with cell constantsa=19.609(5),b=24.513(7),c=15.795(6)Å, β=109.50(2)°,Z=4. The crystal structure was solved inC2 on the basis of 3022 absorption corrected CuKα (Ni-filter) X-ray intensities and refined by full matrix least squares toR=17%. This relatively highR-factor is due to many weak reflections (pseudo-C2) and considerable disorder exhibited by water and iodine. In the complex, β-cyclodextrin adopts a ‘round’ shape with O(2)...O(3) interglucose hydrogen bonds formed and all O(6) hydroxyls pointing away from the cavity. Two molecules are arranged head-to-head to produce a dimer, and dimers are stacked such that a slightly zigzagged cylinder with a 6 Å-wide cavity is formed. In the cavity described by each dimer, an I 7 − ion composed of I2·I 3 − ·I2 units is located, with I2 and I 3 − perpendicular to each other. K+ ions and 9 H2O molecules are found in interstices between the β-cyclodextrin cylinders. This zigzag polyiodide contrasts with the linear form observed in the 5 Å wide α-cyclodextrin channels. It explains differences in color of the crystals and suggests that β-cyclodextrin polyiodide is not a good model for blue starch-iodine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00656821
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  • 2
    Electronic Resource
    Electronic Resource
    Synthese und Reaktionen von (η51-Pentamethylcyclopentadienyl)1- und (η51-Ethyltetramethylcyclopentadienyl)titantrifluorid (1993)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 913-919 
    Details
    ISSN: 0009-2940
    Keywords: Organometallic fluorides ; Titanium ; π1-Complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Preparation and Reactions of (η51-Pentamethylcyclopentadienyl)1- and (η51-Ethyltetramethylcyclopentadienyl)titanium Trifluoride[1]Compound Cp*TiCl3 (1, Cp*=η51-Me5C5) reacts with an excess of AsF3 to yield the crystalline complex [Cp*TiF3]2·2 AsF3 (2). AsF3 can be removed from 2 in vacuo to give Cp*TiF3 (3). Complex (η51-EtMe4C5)TiCl3 (4) is converted by an excess of AsF3 to (η51-EtMe4C5)TiF3 (5). Compound 3 reacts with a lithium 1,3-diketonate to form the hexacoordinated complex (6) and with a lithium benzamidinate to yield pentacoordinated Cp*TiF2[(Me3SiN)2 C-C6H4OMe-(4)] (7): The reaction of 3 with Ph3PNSiMe3 and C2H2(Ph2PNSiMe3)2 leads to Cp*TiF2NPPh3 (8) and (Cp*TiF2NPPh2)2C2H2 (9), respectively. X-Ray structure analyses of compounds 2 and 5-9 have been performed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19931260410
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  • 3
    Electronic Resource
    Electronic Resource
    Addukt eines fünfgliedrigen Trischwefeldistickstoffdioxid-Rings an Titantetrachlorid (1990)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 1345-1346 
    Details
    ISSN: 0009-2940
    Keywords: Sulphur-nitrogen ring ; Titanium ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Adduct of a Five-Membered Trisulfurdinitrogen Dioxide Ring with Titanium TetrachlorideReaction of S6N4O4 with TiCl4 lead to [(S3N2O2)TiCl4]2 (2). Single crystals of 2 were obtained by recrystallization from liquid SO2. 2 forms chains of five-membered S3N2O2 rings connected by Ti2Cl8 units. The S2N2 part of the five-membered ring may be described as a 6-π electron system.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19901230623
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  • 4
    Electronic Resource
    Electronic Resource
    Metallacyclodisiladiazanes of Titanium and zirconium; Synthesis, Structure and Polymerization Studies (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 399-404 
    Details
    ISSN: 0009-2940
    Keywords: Disilylamides ; Group 4 Complexes ; Polymerization ; Metallacycles ; Titanium ; Zirconium ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of metallacyclodisiladiazanes has been prepared. Lithiated (SiMe2NHtBu)2 (1) reacts with TiCl4 · 2 THF to give (SiMe2NtBu)2TiCl (4). Methylation or fluorination of 4 leads to (SiMe2NtBu)2TiMe2 (8) and (SiMe2MtBu)2TiF2 (9), respectively. The reaction of ZrCl4 · 2 THF with lithiated 1 or [SiMe2NH(4-FC6J4)]2 (2) yields (SiMe2NtBu)2ZrCl2 (5) and [SiMe2N(4-FC6H4)]ZrCl2 · THF (7), respectively. The lithiated ligand [SiMe2NH(2,6-iPr2C6H3)]2 (3) reacts with noncoordinated ZrCl4 to give [SiMe2N(2,6-iPr2C6H3)]2ZrCl2 (6). X-ray structural analysis of 9 showed it to be a fluorine-bridged dimer in the solid state. Compounds 4, 6, 8 and 9 were found to be catalysts for the polymerization of ethylene.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300314
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  • 5
    Electronic Resource
    Electronic Resource
    Preparation and Structural Investigations of (dippNSiMe3Si)2(Cp*Ti)2(NH)6 (dipp = 2,6-iPr2C6H3), [dippNSiMe3Si(NH2)NH]3 and [dippNSiMe3Ge(NH2)NH]3 (1999)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 863-867 
    Details
    ISSN: 1434-1948
    Keywords: Germanium ; Nitrogen ; Silicon ; Titanium ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of dippNSiMe3Si(NH2)3 (1) (dipp = 2,6-iPr2C6H3) with Cp*TiMe3 (Cp* = C5Me5) and Me3SnCl yields the new heterocyclic adamantane (dippNSiMe3Si)2(Cp*Ti)2(NH)6 (2) containing the Si2Ti2(NH)6 core and the silicon-nitrogen six-membered ring compound [dippNSiMe3Si(NH2)NH]3 (4). [dippNSiMe3Ge(NH2)2]2NH (5) reacts with AlMe3 to give the germanium-nitrogen six-membered ring compound [dippNSiMe3Ge(NH2)NH]3 (6). The compounds 2, 4 and 6 have been structurally characterized by single-crystal X-ray structural analysis.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Neue Komplexe des Titans mit Bis(trimethylsilyl)amido-LigandenProfessor Kurt Dehnicke zum 60. Geburtstage gewidmet (1991)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 595 (1991), S. 21-26 
    Details
    ISSN: 0044-2313
    Keywords: Titanium complex compounds ; cyclopentadienyl titanium bis(trimethylsilyl)amido compounds ; syntheses ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Complexes of Titanium with Bis(trimethylsilyl)amido LigandsThe reaction of cp′TiCl3 with LiN(SiMe3)2 · Et2O 1 yield the compounds cp′TiCl2N(SiMe3)2 (cp′ = C5H5 2, C5H4SiMe3 3, C5H3(SiMe3)2 4, C5Me5 5) and cp′TiCl[N(SiMe3)2]2 (cp′ = C5H5 6). Compound 2 was characterized by an X-ray structural analysis with space group P21/n and unit cell dimensions of a = 1 660.9(7), b = 688.6(3), c = 1 739.1(8) pm and β = 117.18(3)°.
    Notes: Die Reaktion von cp′TiCl3 mit LiN(SiMe3)2 · Et2O 1 führt zu den Verbindungen cp′TiCl2N(SiMe3)2 (cp′ = C5H5 2, C5H4SiMe3 3, C5H3(SiMe3)2 4, C5Me5 5) und cp′TiCl[N(SiMe3)2]2 (cp′ = C5H5 6). Verbindung 2 wurde durch eine Einkristall Röntgenstrukturanalyse charakterisiert. 2 kristallisiert in der Raumgruppe P21/n mit a = 1 660,9(7), b = 688,6(3), c = 1 739,1(8) pm und β = 117,18(3)°.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19915950104
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