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  • 1
    Electronic Resource
    Electronic Resource
    Wanzlick-Carbene in der [4 + 1]-Cycloaddition mit Bis(methylthio)- und Bis(trifluormethyl)-1,2,4,5-tetrazin (1994)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 127 (1994), S. 1803-1806 
    Details
    ISSN: 0009-2940
    Keywords: Singlet carbenes ; [4 + 1] Cycloadditions ; 1,2,4,5-Tetrazines ; SEAr reactions, intramolecular ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Wanzlick Carbenes in the [4 + 1] Cycloaddition Reaction with Bis(methylthio)- and Bis(trifluoromethyl)-1,2,4,5-tetrazineThe 3,6-disubstituted 1,2,4,5-tetrazines 3 and 4 have been submitted to a [4 + 1] cycloaddition reaction with the nucleophilic singlet carbenes (Wanzlick carbenes) 2a-d, which are generated from the precursors 1a-d. With 3 as diazadiene the expected spiro compounds 6a-d are formed. In contrast to this presumed two-step reaction sequence of 3, with the tetrazine 4 the cascade cycloaddition/cycloelimination is surprisingly followed by an intramolecular electrophilic aromatic substitution to yield the chiral tetracyclic compounds of type 8 with high diastereoselectivity. The crystal structure of 8d has been determined by X-ray diffraction methods.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19941270933
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  • 2
    Electronic Resource
    Electronic Resource
    Azaazulene als Dienophile in der Diels-Alder-Cycloaddition mit 3,6-Bis(trifluormethyl)1-1,2,4,5-tetrazin (1993)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 441-445 
    Details
    ISSN: 0009-2940
    Keywords: Azaazulenes ; 1,2,4,5-Tetrazine ; [4 + 2] Cycloadditions, “inverse” ; Azaazulene-quinoline rearrangement ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Azaazulenes as Dienophiles in the Diels-Alder Cycloaddition with 3,6-Bis(trifluoromethyl)1-1,2,4,5-tetrazineThe LUMO-diene-controlled [4 + 2] cycloaddition of the azaazulenes 6 and 17 with the tetrazine 1, one of the most reactive diazadienes “with inverse electron demand”, are described. Like azulene (2) the azaazulenes 6a, b react with 1 - probably by a two-step mechanism via the dipolar species 7 - to yield the adduct 8; N2 elimination leads to 9, which rearranges to the pyridazo[4,5-c]quinoline 13 and the azine-substituted 1-azaazulene 12. In a rather complex reaction sequence the 2-azaazulene 17 forms the salt 18; the crystal structure of 18 has been determined by X-ray diffraction methods.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19931260222
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  • 3
    Electronic Resource
    Electronic Resource
    Synthese homochiraler 3-Oxa-2,7-diazabicyclo[3.3.0]octane aus Aminosäuren durch intramolekulare 1,3-dipolare Cycloaddition von Nitronen (1993)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 787-795 
    Details
    ISSN: 0009-2940
    Keywords: Heterobicyclo[3.3.0]octanes, homochiral ; Amino acids ; Nitrones ; Cycloadditions, diastereoselective, intramolecular ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of Homochiral 3-Oxa-2,7-diazabicyclo[3.3.0]octanes from Amino Acids by Intramolecular 1,3-Dipolar Cycloaddition of NitronesN1-Allylamino alcohols 9 were prepared from amino acids by various methods. Swern oxidation of 9 afforded aldehydes 11. By reaction of 11 with N1-alkylhydroxylamines nitrone intermediates 4 were formed which spontaneously underwent an intramolecular 1,3-dipolar cycloaddition to yield the bicyclic compounds 6. The cycloaddition proceeds diastereoselectively furnishing homochiral compounds 6 from homochiral starting materials. The structure of 6aA was confirmed by X-ray structural analysis.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19931260333
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  • 4
    Electronic Resource
    Electronic Resource
    Thermisch induzierte formale [3 + 2]-Cycloadditionen von 3,3-Dimethoxycyclopropen an Triazine, eine neue Synthese von Pyrrolo[1,2-d][1,2,4]triazinen (1993)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 126 (1993), S. 2317-2323 
    Details
    ISSN: 0009-2940
    Keywords: 1,2,4-Triazines ; [3 + 2] Cycloadditions ; Singlet vinylcarbene ; 1,3-Dipole, three-carbon ; Pyrrolo[1,2-d][1,2,4]triazines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermally Induced Formal [3 + 2] Cycloadditions of 3,3-Dimethoxycyclopropene to Triazines, a Novel Synthesis of Pyrrolo[1,2-d][1,2,4]triazinesFormal [3 + 2] cycloaddition reactions of the π-delocalized singlet vinylcarbene/three-carbon 1,3-dipole 8, generated in a reversible, thermal ring opening of the cyclopropenone ketal 7, with a variety of substituted triazines lead to the novel pyrrolo[1,2-d][1,2,4]triazines 9 or 10. Compound 10c is protonated at N-2 by HClO4/HOAc to yield the salt 17c and alkylated at the same position by Meerwein reagent [O(CH3)3BF4] to give 18. 10c reacts smoothly with dimethyl acetylenedicarboxylate to provide the pyrido[2,1-f]pyrrolo[1,2-d][1,2,4]triazines 19 and 20. The pyrrolotriazine 14 in the presence of oxygen, daylight, and silica gel is readily oxidized to the triazine N-oxide 22. The crystal structures of 14, of the protonated species 17c and of the N-oxide 22 have been determined by X-ray diffraction methods.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19931261021
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  • 5
    Electronic Resource
    Electronic Resource
    [SbCl([15]Krone-5)](SbCl6)2 und [BiCI([18]Krone-6)(CH3CN)2](SbCl6)2: Salze mit Antimon(III)- und Bismut(III)-DikationenProfessor Wolfgang Beck zum 60. Geburtstag gewidmet (1992)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 104 (1992), S. 354-356 
    Details
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ange.19921040336
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  • 6
    Electronic Resource
    Electronic Resource
    Die Kristallstrukturen der Polyselenide [Cs(18-Krone-6)]2Se5 · DMF, [Rb(222-Crypt)]2Se6, [Ba(15-Krone-5)2]Se6 · DMF und [Na(12-Krone-4)2]2Se7Professor Dietrich Mootz zum 60. Geburtstage gewidmet (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 1247-1256 
    Details
    ISSN: 0044-2313
    Keywords: Polyselenides ; Synthesis ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal Structures of the Polyselenides [Cs(18-Crown-6)]2Se5 · DMF, [Rb(222-Crypt)]2Se6, [Ba(15-Crown-5)2]Se6 · DMF, and [Na(12-Crown-4)2]Se7.The title compounds have been prepared by reactions of the corresponding diselenides with excess selenium in the presence of crown ethers in dimethylformamide solutions, forming black crystals.[Cs(18-Crown-6)]2Se5 · DMF: Space group P21/m, Z = 2, 2 194 observed unique reflections, R = 0.119. Lattice dimensions at 20°C: a = 1 041.2; b = 1 496.3; c = 1 459.7 pm; β = 100.39°. The compound forms an ionic triple with Cs…Se-contacts between 374 and 381 pm.[Rb(222-Crypt)]2Se6: Space group P1, Z = 2, 7 405 observed unique reflections, R = 0.056. Lattice dimensions at - 70°C: a = 1 106.8; b = 1 460.8; c = 1 718.8 pm; α = 89.22°; β = 86.65°; γ = 71.53°. The compound contains Se62- chains without direct contact with each other.[Ba(15-Crown-5)2]Se6 · DMF: Space group P21/n, Z = 4, 2 680 observed unique reflections, R = 0.055. Lattice dimensions at - 80°C: a = 1 051.9; b = 1 322.4; c = 2 729.9 pm; β = 100.93°. The compound contains Se62- chains, which are isolated from each other by the cations and the included DMF molecules.[Na(12-Crown-4)2]2Se7: Space group P1, Z = 2, 7 313 observed unique reflections, R = 0.042. Lattice dimensions at - 70°C: a = 1 260.9; b = 1 433.6; c = 1 462.9 pm; α = 80.27°; β = 78.60°; γ = 69.34°. The compound contains Se72- chains without direct contacts with each other.
    Notes: Die Titelverbindungen entstehen aus den entsprechenden Diseleniden mit überschüssigem Selen in Gegenwart von Kronenethern in Dimethylformamid-Lösungen in Form schwarzer Kristalle.[Cs(18-Krone-6)]2Se5 · DMF: Raumgruppe P21/m, Z = 2, 2 194 beobachtete unabhängige Reflexe, R = 0,119. Gitterabmessungen bei 20°C: a = 1 041,2; b = 1 496,3; c = 1 459,7 pm; β = 100,39°. Die Verbindung bildet ein Ionentripel mit Cs…Se-Kontakten zu dem kettenförmigen Se52--Ion von 374 bis 381 pm.[Rb(222-Crypt)]2Se6: Raumgruppe P1, Z = 2, 7 405 beobachtete unabhängige Reflexe, R = 0,056. Gitterabmessungen bei - 70°C: a = 1 106,8; b = 1 460,8; c = 1 718,8 pm; α = 89,22°; β = 86,65°; γ = 71,53°. Die Verbindung enthält kettenförmige Se62--Ionen, die keine Kontakte untereinander ausbilden.[Ba(15-Krone-5)2]Se6 … DMF: Raumgruppe P21/n, Z = 4, 2 680 beobachtete unabhängige Reflexe, R = 0,055. Gitterabmessungen bei - 80°C: a = 1 051,9; b = 1 322,4; c = 2 729,9 pm; β = 100,93°. Die Verbindung enthält kettenförmige Se62--Ionen, die im Gitter durch die Kationen und die eingelagerten DMF-Moleküle voneinander isoliert sind.[Na(12-Krone-4)2]2Se7: Raumgruppe P1, Z = 2, 7 313 beobachtete unabhängige Reflexe, R = 0,042. Gitterabmessungen bei - 70°C: a = 1 260,9; b = 1 433,6; c = 1 462,9 pm; α = 80,27°; β = 78,60°; γ = 69,34°. Die Verbindung enthält kettenförmige Se72--Ionen, die keine direkten Kontakte untereinander ausbilden.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19936190717
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  • 7
    Electronic Resource
    Electronic Resource
    Synthese, Kristallstruktur und 121Sb-Mößbauer-Spektrum von [SbCl2(18-Krone-6)]+SbCl6- (1992)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 618 (1992), S. 93-97 
    Details
    ISSN: 0044-2313
    Keywords: Crown ether complex of antimony ; synthesis ; 121Sb-Mössbauer spectrum ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Crystal Structure, and 12Sb-Mössbauer Spectrum of [SbCl2(18-Crown-6)]+SbCl6-The title compound, which has been prepared by the reaction of antimony trichloride and antimony pentachloride in the presence of 18-crown-6 in acetonitrile solution, is characterized by its 121Sb-Mössbauer spectrum and by an X-ray structure determination. Space group P21, Z = 2, 2439 observed unique reflections, R = 0.045, wR = 0.043. Lattice dimensions at -80°C: a = 780.6(7), b = 1297.5(9), c = 1 278.5(10) pm, β = 100.56(7)°. The structure of [SbCl2(18-crown-6)]+SbCl6- contains cations in which the antimony atom in the first coordination sphere is surrounded in a φ-trigonal-bipyramidal fashion by two oxygen atoms of the crown ether in axial position as well as in the equatorial position by the two chlorine atoms and the lone electron pair.
    Notes: Die Titelverbindung entsteht aus Antimontrichlorid und Antimonpentachlorid in Gegenwart von 18-Krone-6 in Acetonitrillösung. Sie wird durch ihr 121Sb-Mößbauer-Spektrum und durch eine röntgenographische Strukturanalyse charakterisiert. Raumgruppe P21, Z = 2, 2439 beobachtete unabhängige Reflexe, R = 4,50%, wR = 4,25%. Die Gitterkonstanten betragen bei -80°C: a = 780,6(7); b = 1 297,5(9); c = 1 278,5(10) pm, β = 100,56(7)°. [SbCl2(18-Krone-6)]+SbCl6- enthält Kationen, in denen das Antimonatom in erster Koordinationssphäre φ-trigonal-bipyramidal von zwei O-Atomen des Kronenethers in Axialposition und von den beiden Cl-Atomen sowie dem freien Elektronenpaar äquatorial umgeben ist.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19926180117
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  • 8
    Electronic Resource
    Electronic Resource
    Synthese und Kristallstrukturen der Phosphanimin-Komplexe MCl2(Me3SiNPMe3)2 mit M = Zn und Co, und CoCl2(HNPMe3)2 (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 431-437 
    Details
    ISSN: 0044-2313
    Keywords: Phosphaneimine Complexes of Zinc and Cobalt ; Synthesis ; IR spectra ; Crystal Structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses and Crystal Structures of the Phosphaneimine Complexes MCl2(Me3SiNPMe3)2 with M = Zn and Co, and CoCl2(HNPMe3)2The molecular complexes MCl2(Me3SiNPMe3)2 (M = Zn, Co) have been prepared by the reaction of the dichlorides of zinc and cobalt with Me3SiNPMe3 in CH3CN and CH2Cl2, respectively, whereas the complex CoCl2(HNPMe3)2 has been prepared by the reaction of CoCl2 with NaF in boiling acetonitrile in the presence of Me3SiNPMe3. All complexes were characterized by IR spectroscopy and by crystal structure determinations. The complexes MCl2(Me3SiNPMe3)2 crystallize isotypically.ZnCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 2677 observed unique reflections, R = 0.024. Lattice dimensions at -70°C: a = 1243.6; b = 1319.0; c = 1464.7 pm.CoCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 3963 observed unique reflections, R = 0,071. Lattice dimensions at -80°C: a = 1236.3; b = 1317.4; c = 1457.6 pm.CoCl2(HNPMe3)2 · CH2Cl2: Space group Pbca, Z = 8, 1354 observed unique reflections, R = 0.055. Lattice dimensions at -80°C: a = 1247.3; b = 998.4; c = 2882.4 pm.All complexes have monomeric molecular structures, in which the metal atoms are coordinated in a distorted tetrahedral fashion by the two chlorine atoms and by the nitrogen atoms of the phosphaneimine molecules.
    Notes: Die Molekülkomplexe MCl2(Me3SiNPMe3)2 (M = Zn, Co) entstehen aus den wasserfreien Dichloriden von Zink und Cobalt mit Trimethylsilyl-trimethylphosphanimin in Dichlormethan bzw. Acetonitril, während der Trimethylphosphanimin-Komplex CoCl2(HNPMe3)2 aus CoCl2 mit Natriumfluorid in Gegenwart von Me3SiNPMe3 in siedendem Acetonitril gebildet wird. Die Verbindungen werden durch ihre IR-Spektren und durch Kristallstrukturanalysen charakterisiert. Die Komplexe MCl2(Me3SiNPMe3)2 (M = Zn, Co) sind miteinander isotyp.ZnCl2(Me3SiNPMe3)2: Raumgruppe P212121, Z = 4, Strukturlösung mit 2677 beobachteten unabhängigen Reflexen, R = 0,024. Gitterkonstanten bei -70°C: a = 1243,6; b = 1319,0; c = 1464,7 pm.CoCl2(Me3SiNPMe3)2: Raumgruppe P212121, Z = 4, Strukturlösung mit 3963 beobachteten unabhängigen Reflexen, R = 0,071. Gitterkonstanten bei -80°C: a = 1236,3; b = 1317,4; c = 1457,6 pm.CoCl2(HNPMe3)2 · CH2Cl2: Raumgruppe Pbca, Z = 8, Strukturlösung mit 1354 beobachteten unabhängigen Reflexen, R = 0,055. Gitterkonstanten bei -80°C: a = 1247,3; b = 998,4; c = 2882,4 pm.Alle Komplexe haben monomere Molekülstrukturen, in denen die Metallatome verzerrt tetraedrisch von den beiden Chloratomen und den N-Atomen der beiden Phosphaniminmoleküle koordiniert sind.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19946200305
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  • 9
    Electronic Resource
    Electronic Resource
    Synthese und Kristallstrukturen von (PPh4)2[TeS3] · 2 CH3CN und (PPh4)2[Te(S5)2] (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1046-1050 
    Details
    ISSN: 0044-2313
    Keywords: Trithiotellurate ; Bispentasulfidotellurate(II) ; Preparation ; Crystal Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Crystal Structures of (PPh4)2[TeS3] · 2 CH3CN and (PPh4)2[Te(S5)2](PPh4)2[TeS3] · 2 CH3CN was obtained by the reaction of PPh4Cl, Na2S4 and Te in acetonitrile. With sulfur it reacts yielding (PPh4)2[Te(S5)2]. The crystal structures of both products were determined by X-ray diffraction. (PPh4)2[TeS3] · 2 CH3CN: triclinic, space group P1, Z = 2, R = 0.041 for 4 629 reflexions; it contains trigonal-pyramidal [TeS3]2- ions with an average Te—S bond length of 233 pm. (PPh3)2[Te(S5)2]: monoclinic, P21/n, Z = 2, R = 0.037 for 2 341 reflexions. In the [Te(S5)2]2- ion the tellurium atom has a nearly square coordination by four S atoms. Along with the Te atoms each of the two S5 groups forms a ring with chair conformation.
    Notes: Bei der Reaktion von PPh4Cl, Na2S4 und Te in Acetonitril entsteht (PPh4)2[TeS3] · 2 CH3CN. Mit Schwefel wurde daraus (PPh4)2[Te(S5)2] erhalten. Von beiden Produkten wurden die Kristallstrukturen mittels Röntgenbeugung bestimmt. (PPh4)2[TeS3] · 2 CH4CN: triklin, Raumgruppe P1, Z = 2, R = 4,1% für 4 629 Reflexe; es enthält trigonal-pyramidale [TeS3]2--Ionen mit einer mittleren Te—S-Bindungslänge von 233 pm. (PPh4)2[Te(S5)2]: monoklin, P21/n, Z = 2, R = 3,7% für 2 341 Reflexe. Im [Te(S5)2]2 -Ion ist das Telluratom annähernd quadratisch von vier S-Atomen koordiniert. Jede der beiden S5-Gruppen bildet zusammen mit dem Te-Atom einen Ring in Sesselkonformation.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19946200617
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  • 10
    Electronic Resource
    Electronic Resource
    [SbCl([15]Crown-5)](SbCl6)2 and [BiCl([18]Crown-6)(CH3CN)2](SbCl6)2: Salts with Antimony(III) and Bismuth(III) DicationsDedicated to Professor Wolfgang Beck on the occasion of his 60th birthday (1992)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 31 (1992), S. 334-335 
    Details
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.199203341
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