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
Filter
  • Silicon  (3)
  • (Phosphane)gold(I) complexes  (2)
  • 1
    Electronic Resource
    Electronic Resource
    (Triphenylphosphane)gold(I) Scrambling in a Hexanuclear Complex of Phenylene-1,2-bis(phosphane) (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 217-219 
    Details
    ISSN: 0009-2940
    Keywords: Gold compounds ; (Phosphane)gold(I) complexes ; Clusters ; P Ligands ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Phenylene-1,2-bis(phosphane) reacts with two mole-equivalents of tris[(triphenylphosphane)gold(I)]oxonium tetrafluoroborate in dichloromethane at -78°C to give high yields of a hexanuclear complex {C6H4]P(AuPPh3)3]2}2+ · 2 BF-4 (1). The variable-temperature 31P{1H}-NMR spectra of the product in CD2Cl2 at - 80°C are compatible with a static structure featuring three Ph3PAu units associated with each of the two C6H4P2 phosphide functions, as derived from a clear doublet/quartet pattern. At 50°C in CDCl3, however, there is rapid intramolecular scrambling of these Ph3PAu units, which gives rise to a triplet/septet pattern with the J(P,P) value reduced to exactly one half of the value at the low temperature limit.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300212
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Synthesis Structure and Photoluminescence of 1,2-Disila-acenaphthene Si2C10H10 and 1,2-Diaryldisilane Reference Compounds (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1671-1676 
    Details
    ISSN: 0009-2940
    Keywords: Silicon ; Disilanes ; Diaryldisilanes ; Disilanyl-arenes ; 1,2-Disila-acenaphthene ; Fluorescence spectroscopy ; UV/Vis spectroscopy ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: For the synthesis of the diaryldisilanes Ar-SiH2SiH2-Ar (1a, Ar = phenyl; 1b, Ar = p-tolyl 1c, Ar = mesityl; 1d, Ar = p-anisyl) two convenient preparative routes are reported. The crystal structures of 1c and 1d have been determined in X-ray diffraction studies; the disilanes have a staggered transconformation with a crystallographically imposed center of inversion. For 1a-d no photoluminescence phenomena can be observed. 1,2-Disila-acenaphthene (2) is synthesized in acceptable yield by treatment of 1,8-dilithionaphthalene with 1 equivalent of 1,2-bis[((trifluoromethyl)sulfonyl)oxy]disilane Tf-SiH2SiH2-Tf. The crystal structure of 2 has been determined by X-ray diffraction. The molecule has no crystallographically imposed symmetry but closely follows the symmetry elements of points group C2v. Solutions of 2 exhibit intense fluorescence in the near UV region at room temperature. The fluorescence spectra are discussed in comparison with data on acenaphthene and naphthalene.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971301119
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The Molecular Structures of Tetra(amino)silanes (1997)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 130 (1997), S. 1167-1174 
    Details
    ISSN: 0009-2940
    Keywords: Silicon ; Configuration determination ; Aminosilanes ; Tetra(amino)silanes ; Molecular conformation ; Conformation analysis ; Nitrogen ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In a search for crystalline homoleptic tetra(amin)silanes with (mirror)-symmetrical NR2 substituents, tetrakis( 1-pyrrolidinyl)silane (1) was prepared by an improved synthetic route, and tetrakis(morpholino)silane (2) was synthesized from SiBr4 and morpholine/Li-morpholide via the intermediate BrSi[N(CH2CH2)2O]3 (4). With SiCl4 only the monochloro stage, 3, is reached. Tetrakis(4-methyl-1-piperazinyl)silane (5) was prepared similarly, using 4-methylpiperazine. With (CH2)6NH or (CH2)6NLi and SiBr4 only [(CH2)6N]3SiBr (6) was obtained. The structures of 1, 2 and 5 were determined by single-crystal X-ray diffraction. While compound 1 has an irregular molecular geometry following no symmetrical pattern, molecules of 2 and 5 have similar structures with almost superimposable Si(NC2)4 cores of approximate D2d symmetry. The overall molecular symmetry of 2 is reduced only by incongruous folding of the heterocycles, which are all in a chair conformation. The core structures of 2 and 5 are in excellent agreement with the results of density function calculations for Si(NH2)4. Si(NMe2)4 (the crystal structure of which could not be determined) was converted into (Me2N)3SiO-SO2CF3 (7) by treatment with two equivalents of triflic acid. Reaction of 7 with 1-naphthylamine/triethylamine affords (Me2N)3SiNHC9H7 (8). With 2,4-difluoroaniline/NEt3 the analogous derivative (Me2N)3SiNHC6H3F2 (9) is obtained, but with 4-bromoaniline the product is a silane with the ligands redistributed to give (Me2N2),Si(NHC6H4Br), (10), the structure of which was also determined. It has a non-standard geometry with very flat nitrogen pyramids at all four substituents.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19971300821
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Synthesis and Structure of a Cyclic Complex of Digold Sulfide Au2S and of Related Compounds (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 901-905 
    Details
    ISSN: 0009-2940
    Keywords: Gold sulfide complexes ; Gold thiolates ; (Phosphane)gold(I) complexes ; Digoldsulfonium salts ; Digoldchloronium salt ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4-Bis(diphenylphosphanylmethyl)benzene (1) was converted into its bis[chlorogold(I)] complex [1 · (AuCl)2] upon treatment with two equivalents of chloro(dimethyl sulfide)-gold(I). The reaction of 1 · (AuCl)2 with one equivalent of silver tetrafluoroborate afforded a cyclic di[gold(I)]chloronium tetrafluoroborate [1 · Au2Cl+ BF-4]. Substitution of chloride in 1 · (AuCl)2 by sodium methanethiolate in wet chloroform, gave the bis[methylthiogold(I)] complex 1 · (AuSMe)2], while with sodium sulfide a cyclic complex 1 · Au2S was obtained. Reaction of 1 · (AuCl)2 with two equivalents of AgBF4 followed by treatment with diphenyldisulfide or sodium methanethiolate yielded the cyclic methyl/phenylsulfonium tetrafluoroborates 1 · Au2SPh+ BF-4 and 1 · Au2SMe+BF-4, respectively. All compounds were identified on the basis of their analytical and spectroscopic data. The crystal structures of 1 · (AuCl)2, 1 · (AuSMe)2, and 1 · Au2S have been determined. The Au2S complex has a cyclic structure with a narrow Au-S-Au angle of 86.7(1)° indicating a significant intraannular Au…Au interaction.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19951280908
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The Structural Chemistry of Aziridino- and Azetidinosilanes (1998)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1998 (1998), S. 107-112 
    Details
    ISSN: 1434-1948
    Keywords: Silicon ; Aminosilanes ; Aziridine ; Azetidine ; Molecular conformation ; Configuration determination ; Nitrogen ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In a continuation of structural investigations of poly(amino)silanes, a series of silicon derivatives of aziridine and azetidine have been prepared. Analogies with the isoelectronic phosphorus ylide species and the high barrier to inversion at nitrogen in small N heterocycles were suggestive of steeply pyramidal and rather rigid configurations at the N atoms in the title compounds. Tetrakis(N-aziridino)silane (1) and tetrakis(N-azetidino)silane (2) have been synthesized from SiCl4 and LiN(CH2)x (x = 2, 3). Compound 1 is also formed when LiN(CH2)2 and HSiCl3 are used as starting materials, but with free aziridine a non-volatile product (1a) is obtained. In neither case could any trace of HSi[N(CH2)2]3 be detected. In contrast, RSiCl3 (R = Me, Ph) could readily be converted into the corresponding tris(N-aziridino)silanes (3, 4) by treatment with excess aziridine. Tris(N-azetidino)silane (5) was accessible from HSiCl3 and excess azetidine, but the product was found to contain an unknown impurity. In order to determine the local symmetry and the dynamics of the aziridine rings, 1H-NMR spectra were recorded at low temperature (-80°C). No splitting of the signals was observed, indicating that the inversion barriers are extremely low, even in the highly strained three-membered heterocycles. Nevertheless, single-crystal X-ray diffraction studies of the N-triphenylsilyl derivatives of aziridine (6) and azetidine (7) revealed an aziridinyl group with a steeply pyramidal configuration at nitrogen in 6 (sum of the angles at N 313.32°), and an azetidinyl group with a flat geometry in 7 (sum of the angles at N 350.96°). The Si-N bond is significantly shorter in 7 as compared to that in 6.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...