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  • 1
    Electronic Resource
    Electronic Resource
    Reindarstellung, NMR-Spektren und Kristallstruktur von Triphenylphosphonium-cyclobutylid, (C6H5)3P=C[CH2]3 (1983)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 2173-2179 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis NMR Spectra, and Crystal Structure of Triphenylphosphonium Cyclobutylide, (C6H5)3P=C[CH2]3Crystalline samples of the title compound 2 were obtained from the reaction of (4-bromobutyl)-triphenylphosphonium bromide (1) with sodium amide in liquid ammonia. The NMR data of this salt-free compound indicate significant deviation from a planar carbanion geometry usually typical of unstrained phosphonium ylides. An X-ray diffraction analysis confirms this for the crystalline state. The bond to the approximately tetrahedral onium centre is inclined to the neighbouring plane of the puckered cyclobutane ring (16.7°) by 19.3°. Yet, the ylidic P-C bond of 166.8(3) pm shows significant multiple bond character.
    Notes: Die Umsetzung von (4-Brombutyl)triphenylphosphonium-bromid (1) mit Natriumamid in flüssigem Ammoniak liefert die Titelverbindung 2 in kristalliner Form. Die NMR-Parameter der salzfreien Verbindung zeigen eine deutliche Abweichung von der für spannungsfreie Phosphor-Ylide typischen trigonal-planaren Carbaniongeometrie an. Die Röntgenstrukturanalyse bestätigt dies für den kristallinen Zustand. Das annähernd tetraedrisch konfigurierte Oniumzentrum ragt mit einem Anstellwinkel von 19.3° aus der Ebene des anliegenden Teils des gefalteten Cyclobutanrings (16.7°) heraus. Die ylidische P-C-Bindung besitzt mit 166.8(3) pm noch erheblichen Mehrfachbindungscharakter.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19831160611
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  • 2
    Electronic Resource
    Electronic Resource
    cis-1,2-Diphenylcyclopropan: Molekülstruktur und Versuche zur Chelat-Koordination von Gallium(I) (1988)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1373-1375 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: cis- 1,2-Diphenylcyclopropane; Molecular Structure and Attempted Chelate Complexation of Gallium (I)In an attempt to design a chelating bis(arene) ligand for metals in an s2 electron configuration, the synthesis of cis-1,2-diphenylcyclopropane (1) from ω-benzylideneacetophenone and hydrazine hydrate (followed by pyrolysis) has been optimized. The crystal structure of 1 has been determined by X-ray diffraction [orthorhombic, space group P212121, a = 5.823(1), b = 11.962(2), c = 15.727(3) Å, Z = 4]. The molecules have the expected geometry and dimensions and appear to be ideally suited for complexation of cations like Ga+, as judged from the geometries encountered with non-chelating bis(arene) complexes. 71Ga-NMR spectra of solutions of equimolar quantities of 1 and Ga[GaX4] (X = Cl, Br) in benzene indeed indicate the presence of complexes with monoalkylated arenes, but no crystalline products could be isolated.
    Notes: Im Zuge von Bemühungen um einen Bis(aren)-Liganden, der in der Lage ist, s2-konfigurierte Metalle zu chelatisieren, wurde die Synthese von cis-1,2-Diphenylcyclopropan (1) aus ω-Benzylidenacetophenon und Hydrazin mit nachfolgender Pyrolyse optimiert und die Kristallstruktur dieses Kohlenwasserstoffs bestimmt [orthorhombisch, Raumgruppe P212121, a = 5.823(1), b = 11.962(2), c = 15.727(3) Å, Z = 4]. Die Moleküle besitzen die erwartete Geometrie mit den im voraus abgeschätzten Dimensionen und sollten speziell für die Chelatisierung von Ga(I) geeignet sein. 71Ga-NMR-Daten von Lösungen äquimolarer Mengen 1 und Ga[GaX4], X = Cl, Br, in Benzol zeigen in der Tat die erwartete Komplexbildung an monoalkylierte Aromaten an, es konnten aber keine kristallinen Produkte isoliert werden.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19881210802
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  • 3
    Electronic Resource
    Electronic Resource
    Preparation and Crystal Structures of 2-Aminoethyl Phosphate Complexes of Magnesium, Calcium, and Zinc (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 509-513 
    Details
    ISSN: 0009-2940
    Keywords: 2-Aminoethyl phosphate complexes ; Magnesium complexes ; Calcium complexes ; Zinc complexes ; Hydrogen bonding ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crystalline magnesium, calcium, and zinc 2-aminoethyl phosphate complexes containing the monoanions PEAH⊖ have been prepared as the tetrahydrates (Ca, Zn) and the hexahydrate (Mg), and their structures determined by single-crystal X-ray methods. The structures of monoclinic Ca(PEAH)2·4 H2O and Zn(PEAH)2·4 H2O (space group C2/c) both contain polymeric chains with metal ions connected by bridging phosphate groups. The zinc atoms are in a tetrahedral environment of four oxygen atoms, while the calcium atoms are found to be hexacoordinated with two additional oxygen atoms from water molecules in axial positions. The triclinic Mg(PEAH)2·6 H2O (space group \documentclass{article}\pagestyle{empty}\begin{document}$ P\bar 1 $\end{document}) contains discrete complex units with hexacoordinate magnesium atoms octahedrally surrounded by six oxygen atoms, four of which from water molecules in the equatorial plane and two from phosphate groups in axial positions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240315
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  • 4
    Electronic Resource
    Electronic Resource
    New Organophosphorus Ligands: Cyclopropanation and Other Reactions of Cumulenes Bearing Diphenylphosphanyl Substituents (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 365-371 
    Details
    ISSN: 0009-2940
    Keywords: Cumulenes ; Butadienes ; Vinylcyclopropane ; Vinylidenecyclopropane ; Bicyclopropyl, phosphanyl-substituted ; Cyclopropanation ; Phosphane ligands ; Phosphane chalcogenides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hydrophosphorylation of 1,4-bis(diphenylphosphanyl)butadiyne with diphenylphosphane leads to the butadiene (Ph2P)2C=CH—CH=C(PPh2)2 (1). Treatment of 1 with dimethylsulfonium methylide gives the vinylcyclopropane (Ph2P)2C=CH—CH(CH2)C(PPh2)2 (2). Compound 2 reacts with aqueous hydrogen peroxide, elemental sulfur, or selenium to afford the tetrachalcogenides (Ph2XP)2C=CH—CH(CH2)C(PXPh2)2 with X = O (3), X = S (4), X = Se (5), respectively. While the tetraphosphane 1 and the vinyl-cyclopropane compound 2 cannot be converted into a bis-(cyclopropyl) compound with an excess of Me2S=CH2, the tetrasulfide 4 readily affords a mixture of (1R,1′R)-/(1S,1′S)-and meso-2,2,2′,2′-tetrakis(diphenylthiophosphinyl)-1,1′-bicyclopropyl (6, 7) in good yield. Treatment of 1,1,4,4-tetrakis-(diphenylphosphanyl)butatriene with dimethylsulfonium methylide leads to the vinylidenecyclopropane (Ph2P)2C=C=C(CH2)C(PPh2)2 (8). Compound 8 is converted into its tetrasulfide (Ph2SP)2C=C=C(CH2)C(PSPh2)2 (9) by treatment with elemental sulfur. The crystal structures of 1, 2, 4, 7, and 8 have been determined by single-crystal X-ray diffraction.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280408
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  • 5
    Electronic Resource
    Electronic Resource
    The Molecular Structures of Triaminosilanes (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1159-1166 
    Details
    ISSN: 0009-2940
    Keywords: Aminosilantes ; Structure elucidation ; Molecular conformations ; Configuration determination ; Nitrogen Planarity/Silanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structural chemistry of a series of triaminosilanes XSi(NR2)3 has been investigated in order to determine the ground-state configuration and conformation of these molecules. Theoretical studies and analogy with the isoelectronic XP(NR2)3 (X = CH2, O, Se, NSiMe3 etc.) and P(NR2)3 molecules suggest structures of Cs or C3 symmetry, with small energy differences between them. The molecular structure of HSi(NMe2)3 (1) has been determined by a single-crystal X-ray diffraction study at low temperature. Surprisingly, the molecules have a non-standard conformation with an irregular orientation of the three NMe2 groups. The hydrido-, chloro-, methyl-, and vinyltris(morpholino)silanes XSi[N(CH2CH2)2O]3 (X = H, Cl, Me, Vi; 2-5) were prepared from the corresponding chlorosilanes and morpholine (2, 3) or lithium morpholide (4,5). Their variable-temperature NMR spectra were studied and the molecular structures determined by single crystal X-ray diffraction. Compound 2 has a molecular geometry approaching mirror symmetry with one morpholino group significantly different from the other two. This structure resembles that of isoelectronic tris(amino)phosphines. Compounds 3-5 have structures with a propeller-like arrangement of the three morpholino rings approaching C3 symmetry for this part of the molecules. The chloro compound 3 shows the shortest Si-N bond lengths (average 1.690 Å), followed by 2 (1.708Å),5 (1.709Å) and 4 (l.712Å). The configuration of all nitrogen atoms is almost planar, with sums of the angles close to 360°, and the morpholino rings adopt a chair conformation. According to the solution NMR spectra the ring inversion is slow at low temperature, but the rings rotate freely about the Si-N bonds on the NMR time scale. The molecular structures are discussed in terms of steric and electronic effects of the substituents. Other model compounds, including (Me2N)3SiC6H4-4-Br (6), MeSi[N(CH2CH2)2NMe]3 (7) and PhSi[N(CH2)4]3 (8), could not be crystallized, but were characterized by their analytical and spectroscopic data.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300820
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  • 6
    Electronic Resource
    Electronic Resource
    Tris(dimethylamino)phosphane as a New Ligand in Gold(I) Chemistry: Synthesis and Crystal Structures of [(Me2N)3P]AuCl, {[(Me2N)3PAu]3O}+BF4-, {[Me2N)3PAu]3NP(NMe2)32+ {BF-4}2 and the Precursor Molecule (Me2N)3PNSiMe3 (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 323-328 
    Details
    ISSN: 0009-2940
    Keywords: Gold ; Phosphanes ; Phosphaneimines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [Tris(dimethylamino)phosphane]gold(I) chloride, μ-tris-{[tris(dimethylamino)phosphane]gold(I)}oxonium tetrafluoroborate, {μ3-tris(dimethylamino)phosphaneimidotris[tris(dimethylamino)phosphane]gold(I)}(2+) bis(tetrafluoroborate) and N-trimethylsilyltris(dimethylamino)phosphaneimine were prepared using modifications of established procedures. Their structures were determined in single-crystal X-ray diffraction studies. The ligand (Me2N)3P, here introduced into gold(I) chemistry for the first time, lends high stability to these compounds through efficient steric shielding of the reaction sites and through a balanced electronic substituent effect. The structural details of the (Mr2N)3P groups are of current interest because of the unusual nonequivalent configuration of the nitrogen atoms in the dimethylamino groups. This behaviour has been observed for most of the (Me2N)3P units in the compounds studied in this work.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300304
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  • 7
    Electronic Resource
    Electronic Resource
    Ylid-Bildung aus Cyclopropyl-/Isopropylphosphonium-Salzen: Eine Verletzung der CH-Aciditäts-Regel (1984)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 2314-2321 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ylide Formation from Cyclopropyl/Isopropylphosphonium Salts: A Violation of the CH-Acidity RuleContrary to predictions from the CH-acidity rule, deprotonation of phosphonium cations [(i-Pr)n(c-Pr)4 - nP]⊕ containing both isopropyl and cyclopropyl substituents leads exclusively to ylides with the open-chain isopropylide group. Evidently, the pyramidal carbanion geometry of cyclopropylides is much less favoured than the planar carbanion geometry of isopropylides.
    Notes: Bei der Deprotonierung von Phosphonium-Kationen [(i-Pr)n(c-Pr)4 - nP]⊕, die gleichzeitig Isopropyl- und Cyclopropyl-Substituenten tragen, werden entgegen der Aciditätsregel ausschließlich die Ylide mit der offenen Isopropylid-Gruppe gebildet. Offenbar ist die pyramidale Carbanion-Geometrie der Cyclopropylid wesentlich ungünstiger als die planare Carbanion-Geometrie der Isopropylide.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19841170704
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  • 8
    Electronic Resource
    Electronic Resource
    Olefin- und Cyclopropan-Aktivierung durch geminale Phosphonium-Zentren (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3105-3113 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Olefin and Cyclopropane Activation Through Geminal Phosphonium CentresComplete quaternization of vinylidenebis(diphenylphosphane) (1) with CH3I or CH3OSO2F yields the diquaternary salts 2a,b, whose olefinic double bond is strongly electrophilic through the activation by two geminal phosphonium centres. Accordingly, addition of methanol or ethanol to 2a,b leads to β-alkoxy-substituted double phosphonium salts 9a-i. The structure of one of these products (9a: X=I, R=CH3) was elucidated by single crystal X-ray diffraction analysis. Spectroscopic data are provided for the remaining compounds. - Treatment of triphenylphosphonium cyclopropylide (5) with chlorodiphenylphosphane gives the gem-phosphinosubstituted salt 6, which can be quaternized with CH3OSO2F to yield a bis-phosphonium salt (7a,b). A symmetrical homologue 7c is formed from cyclopropylidenebis(diphenylphosphane) (8) and CH3OSO2F. In 7a-i the cyclopropane cycle is also clearly activated. Ring cleavage occurs with alcohols leading to γ-alkoxylated salts 10a,b.
    Notes: Die erschöpfende Quartärisierung von Vinylidenbis(diphenylphosphan) (1) mit CH3I oder CH3OSO2F liefert Diquartärsalze 2a,b, deren olefinische Doppelbindung durch die beiden Phosphonium-Zentren stark elektrophil aktiviert ist. Die Addition von Methanol oder Ethanol an 2a,b liefert entsprechend die β-alkoxysubstituierten Doppelphosphonium-Salze 9a-i. Die Struktur eines dieser Produkte (9a: X=I, R=CH3) wurde durch eine Einkristall-Röntgenbeugungsanalyse gesichert, für die übrigen liegen spektroskopische Daten vor. - Triphenylphosphoniumcyclopropylid (5) ergibt mit (C6H5)2PCl das geminal phosphinosubstituierte Salz 6, das durch CH3OSO2F zum Bisphosphonium-Salz quartärisiert werden kann (7a,b). Ein symmetrisches Homologes 7 c entsteht aus Cyclopropylidenbis(diphenylphosphan) (8) und CH3OSO2F. In 7a-i ist der Cyclopropan-Cyclus ebenfalls deutlich elektrophil aktiviert. Mit Alkoholen tritt Ringspaltung ein, die hier zu γ-alkoxylierten Salzen 10a,b führt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180809
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  • 9
    Electronic Resource
    Electronic Resource
    Synthesis of the Hexakis[(triphenylphosphane)gold(I)]methanium(2+) Cation from Trimethylsilyldiazomethane; Crystal Structure Determination of the Tetrafluoroborate Salt (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 111-114 
    Details
    ISSN: 0009-2940
    Keywords: Gold clusters ; Silyldiazomethane ; Auration ; Interstitial carbon atom ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new synthetic route to the bis(tetrafluoroborate) salt of the hexakis[(triphenylphosphane)gold(I)]methanium dication has been opened up through the reaction of trimethylsilyldiazomethane and tris[(triphenylphosphane)gold(I)]oxonium tetrafluoroborate in dichloromethane. Yields are close to 65% if the reaction is carried out in the presence of triethylamine as a base. The process is a sequence of desilylation, deprotonation and deazotation reactions at the carbon function of the diazomethane, as shown by the detection of intermediates. The crystal structure of the title compound (with three equivalents of crystal dichloromethane) has been determined in a single-crystal X-ray study. The dication has no crystallographically imposed symmetry, but the core is a distorted, carbon-centered octahedron of gold atoms. This result confirms the data from previous structural studies of salts with other anions and interstitial solvents.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300118
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  • 10
    Electronic Resource
    Electronic Resource
    Polygold(1-adamantyl)ammonium Salts (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 221-223 
    Details
    ISSN: 0009-2940
    Keywords: Gold ; Polygoldammonium salts ; (1-Adamantyl)ammonium salts ; Trinuclear complex, X-ray structure of ; Tetranuclear complex ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of 1-adamantylamine with tris(triphenylphosphaneaurio)oxonium tetrafluoroborate results in the formation of the trinuclear adamantyltris(triphenylphosphaneaurio)ammonium tetrafluoroborate {C10H15[Au(PPh3)]3}+BF4-. The product can be further aurated by addition of equimolar amounts of triphenylphosphanegold(I) tetrafluoroborate to give the tetranuclear complex {C10H15N[Au(PPh3)]4}2+(BF4minus;)2. Both compounds have been fully characterized by analytical and spectroscopic data, and in the case of the trinuclear complex by a single crystal X-ray structure determination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300213
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