Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Metal Ion Binding by Amino Acids. Potassium Hydrogen L-Glutamate Monohydrate K(L-GluH)·H2O (1990)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 1001-1004 
    Details
    ISSN: 0009-2940
    Keywords: Amino acid complexes ; L-Glutamate complexes ; Hydrogen L-glutamate complexes ; Potassium hydrogen L-glutamate ; Hydrogen bonding ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The title compound is obtained by neutralization of aqueous solutions of L-glutamic acid with potassium hydroxide, and crystallization from aqueous methanol. The compound shows a pH of 7 in water at ambient temperature and an optical rotation [α]20D of -4.30 (c = 3.0). In the crystal (orthorhombic, space group P212121) the potassium ion is in a distorted trigonal-prismatic environment of six oxygen atoms of four different amino acids and of the water molecule. No nitrogen coordination is observed. Through the bridging function of some of the α-carboxylate oxygen atoms (O1, O2) and through complexation of the metal through the γ-carboxylate groups (O3), a layer-coordination polymer, with strings of potassium ions running parallel, is formed. The layers are cross-linked by hydrogen bonds involving the ammonium and γ-carboxylate functions as well as the water molecule.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19901230512
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Synthetic pathways to disilylmethane, H3SiCH2SiH3, and methyldisilane, CH3SiH2SiH3 (1990)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 2087-2091 
    Details
    ISSN: 0009-2940
    Keywords: Disilylmethane ; Methyldisilane ; Silanes ; Silicon carbide, hydrogenated, amorphous (a-SiC:H) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Disilylmethane is available in a four-step synthesis starting with phenylsilane. This is converted into chlorophenylsilane by HCl/AlCl3. The reaction of PhSiH2Cl and dibromomethane with magnesium in tetrahydrofuran affords bis(phenylsilyl)-methane, which yields bis(bromosilyl)methane by treatment with anhydrous hydrogen bromide. (BrH2Si)2CH2 is converted into disilylmethane by reduction with LiAlH4 in a two-phase system using a phase-transfer catalyst. - Methyldisilane is available by alkylation of a monohalodisilane, XSi2H5 (X = Cl, Br), with methyllithium in a high-boiling ether or by silylation of bromomethylsilane with silylpotassium. Due to secondary silylation reactions the overall yields of methyldisilane are low in all cases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19901231102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Arsen(III)-, Antimon(III)- und Bismuth(III)-halogenid-Komplexe des [2.2.2]Paracyclophans: Vom lockeren van-der-Waals-Addukt zu stark gerichteten π-Komplexen mit zwei- und dreifacher externer η6-Koordination (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1089-1093 
    Details
    ISSN: 0009-2940
    Keywords: [2.2.2]Paracyclophane ligand ; (η6)π Complexes ; Arsenic(III) complexes ; Antimony(III) complexes ; Bismuth(III) complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Arsenic(III), Antimony(III), and Bismuth(III) Trihalide Complexes of [2.2.2]Paracyclophane: From Weak van der Waals Coordination to Strongly Directional π Complexation with Single or Double External η6 Coordination[2.2.2]Paracyclophane forms the adducts C24H24·AsCl3 (1), C24H24·(SbCl3)2·1/2 C6H6 (2), and C24H24·(BiCl3)3·C6H6 (3). For solutions in polar solvents NMR spectra indicate extensive dissociation and/or fluxionality. In the crystals adduct 1 features a weak addition of the AsCl3 molecule to one open side of a paracyclophane molecule with long intermolecular contacts approaching C3v symmetry. - Crystalline 2 shows SbCl3 coordination to two of the benzene rings of the hydrocarbon in a quasi-centered η6 mode, while one of the benzene rings remains uncoordinated. Chlorine-bridging between antimony atoms leads to tetrameric units (SbCI3)4 in the lattice. - In the bismuth compound 3 each benzene ring of the hydrocarbon is engaged in centroid (η6)π complexation, with the BiCl3 units crosslinked by chlorine bridges. The average of the Bi-ring distances (3.08,2.98, and 2.99 Å) is shorter than for the Sb-ring distances in 2 (3.047 and 3.050 Å), indicating stronger bonding. The crystal benzene is not coordinating.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240516
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Molecular Structure of Trisilylmethane and Synthesis of 1,1,1-Trisilylethane (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1953-1956 
    Details
    ISSN: 0009-2940
    Keywords: Trisilylmethane ; 1,1,1-Trisilylethane ; CVD feedstock gases ; Silicon carbide, hydrogenated, amorphous (a-SiC:H) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: As a precursor for trisilylmethane, tris(phenylsilyl)methane is prepared by a Merker-Scott reaction of chlorophenylsilane, bromoform, and magnesium turnings in boiling tetrahydrofuran. Chlorophenylsilane is formed in a new synthesis starting from phenylsilane and hydrogen choride/AlCl3 in diethyl ether. The gas phase structure of trisilylmethane (H3Si)3CH, obtained from (PhSiH2)3CH via (BrSiH2)3CH, has been determined by electron diffraction. Data refinement confirmed a model of C3 molecular symmetry, with local C3v symmetry for the silyl groups.  -  As a precursor for 1,1,1-trisilylethane, 1,1,1-tris(phenylsilyl)ethane has been prepared similarly from chlorophenylsilane, 1,1,1-trichloroethane and magnesium and converted via 1,1,1-tris(bromosilyl)ethane into CH3C(SiH3)3.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240911
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Cyclic dinuclear gold(I) complexes: The crystal structure of bis-μ-[(diphenylphosphino)(diphenylphosphinoselenoyl)methane]-digold(I) bis(perchlorate) (1990)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 2261-2265 
    Details
    ISSN: 0009-2940
    Keywords: Gold(I) complex ; Phosphine (selenide) complexes ; Aus···Au interactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [(CO)AuCl] reacts with equimolar amounts of Ph2PCH2P(Se)Ph2 (dpmSe) to afford ClAuPh2PCH2P(Se)Ph2, in which dpmSe is bound to gold in a monodentate fashion by phosphorus. Subsequent reaction of this 1:1 complex with AgClO4 results in the formation of the 10-membered ring complex 4 which crystallizes in the monoclinic space group P21/n with approximately centrosymmetric dicationic units, in which two gold (I) atoms are doubly bridged by two dpmSe ligands coordinated by phosphorus and selenium. The coordination at the gold atoms deviates from linearity and implies an Au···Au interaction with the gold(I) atoms separated by a distance of 3.020(1) Å.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19901231206
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Metal Bonding by Amino Acids: Preparation and Crystal Structures of Calcium Bis-L-pyroglutamate and Lithium L-Pyroglutamate (1991)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 1083-1087 
    Details
    ISSN: 0009-2940
    Keywords: Calcium bis-L-pyroglutamate ; Lithium L-pyroglutamate ; Pyroglutamate coordination and conformation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Calcium bis-L-pyroglutamate and lithium L-pyroglutamate are prepared by reaction of the metal hydroxides with L-pyroglutamic acid in aqueous solution. In the solid state calcium bis-L-pyroglutamate adopts a layer structure, built up by sixteen-membered rings consisting of four L-pyroglutamate ligands bridging four calcium centers by their carboxylate groups. All three oxygen donors of the L-pyroglutamate ligands are attached to metal centers. The calcium atom lies at the center of a slightly distorted octahedron formed by four carboxylate oxygens and two amide oxygen atoms. Lithium L-pyroglutamate also features a layer structure. All three oxygen donors of the L-pyroglutamate ligand have contacts with metal atoms. The coordination sphere of the lithium atom is a slightly distorted tetrahedron consisting of three carboxylate oxygen atoms and one amide oxygen atom. The investigation of aqueous solutions of the compounds by multinuclear NMR (1H, 13C, 17O) indicates extensive electrolytic dissociation in dilute solutions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19911240515
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Metal Binding by Amino Acids: Preparation and Crystal Structures of Lithium, Sodium, and Potassium Hydrogen Bis-L-pyroglutamate (1992)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 1829-1834 
    Details
    ISSN: 0009-2940
    Keywords: Hydrogen bis-L-pyroglutamates, lithium, sodium, potassium ; Pyroglutamate coordination and conformation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Lithium, sodium and potassium hydrogen bis-L-pyroglutamate [Li(L-pGlu)(L-pGluH)], [Na(L-pGlu)(L-pGluH)] and [K(L-pGlu)(L-pGluH)], respectively, have been prepared by reaction of aqueous solutions of the metal hydroxides with L-pyroglutamic acid in the molar ratio 1:2, or in methanol. Crystalline samples of the salts could be obtained by slow evaporation of solutions of the salts in methanol. In the solid state, Li(L-pGlu)(L-pGluH) adopts a chain structure with the lithium atoms arranged in double strands. Adjacent metal centers are bridged by the carboxylate groups of the L-pGlu- ligands. The L-pGluH ligands are attached to the metal centers through the amide oxygen atoms. Na(L-pGlu)(L-pGluH) forms a three-dimensional coordination polymer with two half-occupied sodium positions, one L-pGlu- and one L-pGluH ligand in the asymmetric unit. The carboxyl and carboxylate groups of the L-pGluH and the L-pGlu- ligands are bridging the sodium centers, giving rise to eight-membered rings, which consist of two sodium atoms, a carboxyl and a carboxylate group. The hydrogen atoms of the carboxyl group of the L-pGluH ligands are involved in strong hydrogen bonds between a carboxyl and an adjacent carboxylate oxygen atom. K(L-pGlu)(L-pGluH) adopts a layer structure with strands of potassium atoms. The metal centers are connected through bridging carboxyl and carboxylate groups of the L-pGluH and L-pGlu- ligands, respectively. The structure features eight-membered ring units comparable to those observed for Na(L-pGlu)(L-pGluH), again with the hydrogen atom of the carboxyl group engaged in a strong transannular hydrogen bond. The amide oxygen atoms of the L-pGlu- and the L-pGluH ligands are coordinated to the metal centers of adjacent coordination chains. The results of 1H- and 13C—NMR investigations of aqueous solutions of the compounds indicate extensive electrolytic dissociation in dilute solutions.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19921250808
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Preparation and Structure of Hexakis[(trialkylphosphane)aurio(I)]methanium(2+) Salts [(LAu)6C]2+(X-)2 with L=Et3P, iPr3P and X=BF4-, B3O3F4- (1992)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 2705-2710 
    Details
    ISSN: 0009-2940
    Keywords: Auriophilicity ; Gold(I), phosphane complexes ; Methanium, hexaaurio(I) compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Hexaaurated carbon complexes of the type [(R3PAu)6C](BF4)2, R=Et (2a), iPr (2b) have been prepared by the reaction of the appropriate (phosphane)gold(I) chlorides R3PAuCl (1a and 1b) with tetrakis(dimethoxyboryl)methane, 13C-enriched at the central carbon atom, in the presence of excess of CsF in HMPT at room temperature. The products 2a and 2b are characterized by standard spectroscopic methods including direct detection of the interstitial C atoms by 13C-NMR spectroscopy. The crystal structure of the compound [(iPr3PAu)6C](B3O3F4)2 · 3 CH2Cl2 (3), obtained from partial (anion) hydrolysis has been determined. It contains dications with a central carbon atom surrounded by six (phosphane)gold(I) units. The edges of the CAu6 octahedron represent short Au-Au contacts (aprox. 3.0 Å), which strongly contribute to the formation and stability of these hypercoordinated species. Attempts to prepare a corresponding hexaauriomethanium dication starting from tBu3PAuCl (1c) failed owing to the bulkiness of the (tri-tert-butylphosphane)gold(I) unit. The X-ray structure analysis for 1c verifies an extremely crowded environment of the gold atom with small Au - P - C angles of only 107° leading to efficient shielding of the metal atom by methyl groups.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19921251214
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    A Synthetic Pathway to 1,3-Bis(trisilylmethyl)disiloxane [(H3Si)3CSiH2]2O  -  the Octasila Analogue of Dineopentyl Ether [(H3C)3CCH2]2O (1994)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 1359-1362 
    Details
    ISSN: 0009-2940
    Keywords: Silanes ; Siloxanes ; Si - C bond, selective cleavage ; Arylsilylmethanes ; Si,C,O single-source CVD precursor ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A synthetic route to partly silylated tetra(silyl)methanes (ArH2Si)nC(SiH3)4  -  n′ to their precursors (TfH2Si)nC-(SiH2Ar)4  -  n (Ar = p-tolyl, phenyl; Tf = CF3SO3; n = 3, 2, 1), and to 1,3-bis(trisilylmethyl)disiloxane [(H3Si)3CSiH2]2O (9) is reported. Starting from symmetrical tetrakis(arylsilyl)-methanes (aryl = p-tolyl, phenyl), we have obtained the selectively dearylated (arylsilyl)silylmethanes (ArH2Si)nC(SiH3)4  -  n (Ar = p-tolyl, phenyl; n = 3, 2, 1) by Si - Ar cleavage with equivalent quantities of trifluoromethanesulfonic acid (triflic acid) and hydrogenation of the corresponding silyl triflates (TfH2Si)nC(SiH2Ar)4  -  n (n = 3, 2, 1) with LiAlH4. The synthesis of 9 has been accomplished by treating trisilyl(p-tolylsilyl)methane p-TolH2SiC(SiH3)3 (7) with stoichiometric amounts of triflic acid to give (trisilylmethyl)silyl triflate TfH2SiC(SiH3)3 (8) and hydrolysing the latter with water.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19941270806
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Gold(I) Complexes of Primary Phosphanes: Pair Formation through Au…Au Interactions (1990)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 285-287 
    Details
    ISSN: 0009-2940
    Keywords: Phosphanes, primary / Gold complexes / Gold-gold interactions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (CO)AuCl reacts with (2,4,6-trialkylphenyl)phosphanes 1a-d (alkyl = Me, Et, iPr, tBu) to give the 1:1 complexes 2a-d. The crystal structure of 2d shows pairs of molecules with Au…Au contacts of 3.440(1) Å.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19901230210
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...