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  • 1970-1974  (7)
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  • 1
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to Boron Chemistry. LXV. N- and B-functional 1,2,4-Triaza-3,5-diborolidinesB,B′-difunctional l,2,4-traza-3,5-diborolidines (TADB) can be prepared by substitution from 3,5-bis(methylthio)-l,2,4-triaza-3,5-diborolidines, Hydrido-, chloro-, bromo-, methoxy- and dimethylamino derivatives are described. The bis(methoxy) compound condenses to a polymer with elimination of B(OCH3)3.Tert.-butyllithium metallates 1,2,3,5-tetramethyl-TADB or 2,4,3,5-tetramethyl-TADB at nitrogen 4 and 1 respectively. Reaction of these N-lithio derivatives with organo-element chlorides ([(CH3)2N]2BCl, (CH3)3SiCl, (CH3)3SnCl, [(CH3)2N]2PCl, (CH3)2PCl etc.) yields stable organoelement derivatives of TADB. Comparison of the 11B-NMR-data of these compounds with corresponding derivatives of borazine, diazaborolidines, and bis(dimethylamino)boranes indicates π-electron delocalisation within the 6π-electron system of the TADD ring.
    Notes: B,B′-difunktionelle 1,2,4-Triaza-3,5-diborolidine (TADB) sind durch Substitution von 3,5-Bis(methylthio)-l,2,4-triaza-3,5-diborolidinen darstellbar. Es werden die Hydrido-, Chlor-, Brom-, Methoxy- und Dimethylaminoderivate beschrieben. Die Bis(methoxy)-Verbindung kondensiert leicht unter Abspaltung von B(OCH3)3 zu Polymeren.Die Metallierung von 1,2,3,5-Tetramethyl-TADB bzw. 2,4,3,5-Tetramethyl-TADB gelingt mit tert.-Butyllithium. Umsetzung der N-Lithioderivate mit Organoelement-chloriden ([(CH3)2N]2BCl, (CH3)3SiCl, (CH3)3SnCl, [(CH3)2N]2PCl, (CH3)2PCl u. a.) führt zu stabilen Organoelement-TADB-Derivaten.Ein Vergleich der 11B-NMR-Daten verschiedener BN-Systeme (Borazine, Diazaborolidine, Bis(dimethylamino)borane) deutet auf eine gute Delokalisierung der 6π-Elektronen des TADB-Systems hin.
    Additional Material: 2 Tab.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 373 (1970), S. 36-47 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Diphenylphosphorous chloride and methyl iodide add readily to the N-bonded P(III)-atom of (C6H5)2P—P(C6H5)3=N—P(C6H5)2 forming the salts [(C6H5)2P—P(C6H5)2 N P(C6H5)2—P(C6H5)2]Cl and [(C6H5)2P—P(C6H5)2 N P(C6H5)2. CH3]I, respectively. A similar behaviour is observed with sulfur: Under mild conditions (C6H5)2P—P(C6H5)2=N—P(C6H5)2 = S is formed but forcing conditions are required to produce S = P(C6H5)2—P(C6H5)2=N—P(C6H5)2=S. The monosulfide is also obtained by treating (C6H5)2P(S)N[Si(CH3)3]2 with diphenylphosphorous chloride, indicating the favoured formation of the phosphazene system as compared with the phosphazane system Confirmation of the structures comes from 31P nmr and IR data, and for the sulfides also from their degradation with bromine.
    Notes: Das reaktive Zentrum der Verbindung (C6H5)2P—P(C6H5)2=N—P(C6H5)2 gegenüber elektrophilen Agentien ist das N-gebundene P(III)-Atom: Diphenylphosphorchlorid liefert Octaphenyltetraphosphor-nitrid-chlorid [(C6H5)2P—P(C6H5)2 N P(C6H5)2—P(C6H5)2]Cl, Methyljodid das Salz [(C6H5)2P—P(C6H5)2 N P(C6H5)2CH3]J und Schwefel über das Monosulfid (C6H5)2P—P(C6H5)2=N—P(C6H5)2 = S unter härteren Bedingungen das Disulfid S = P(C6H5)2—P(C6H5)2=N—P(C6H5)2=S. Das Monosulfid entsteht auch bei der Einwirkung von Diphenylphosphorchlorid auf (C6H5)2P(S)N[Si(CH3)3]2. Zut Sicherung der Strukturen wurden neben 31P—KMR- mid IR-Spektren bei den Sulfiden zusätzlich Brom-Abbaureaktionen herangezogen.
    Additional Material: 5 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 397 (1973), S. 247-257 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metal Tetrahydroborates and Tetrahydroboratometallates. VIII. Preparation and Properties of Dimeric Halogenotitanium(III) Bis(tetrahydroborates) [XTi(BH4)2]2Chlorotitanium(III)bis(tetrahydroborate) is produced besides Ti(BH4)3 in the reaction of TiCl4 vapour with solid LiBH4. It forms in 72% yield by using n-pentane as reaction medium. BrTi(BH4)2 and ITi(BH4)2 were prepared similarly. All these compounds are dimerized via halogen bridges. The bridge opens by addition of tetrahydrofurane to ClTi(BH4)2 with disproportionation to yield Ti(BH4)3 · nOC4H8 and TiCl3 · mOC4H8 contrary to diethylether.The ir, 11B-nmr and electronic spectra of the halogenotitanium(III) bis(tetrahydroborates) are discussed.
    Notes: Chloro-titan(III)-bis(boranat) ist neben Ti(BH4)3 Produkt der Reaktion von TiCl4-Dampf mit festem LiBH4; es entsteht als Hauptprodukt (72%) bei der Umsetzung in Pentan. Analog läßt sich BrTi(BH4)2 und JTi(BH4)2 darstellen. Die Verbindungen sind über Halogenbrücken dimerisiert, die im Falle des ClTi(BH4)2 durch Tetrahydrofuran unter Disproportionieren in Ti(BH4)3 · nOC4H8 und TiCl3 · mOC4H8, nicht aber von Äther aufgebrochen werden.Die IR-, 11B-nmr- und Elektronenspektren der Verbindungen werden diskutiert.
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  • 4
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The systems LiBH4/Al(BH4)3/diethylether and LiBH4/Al(BH4)3/tetrahydrofuran have been investigated by 11B nmr measurements. Temperature dependent spectra at various concentrations and mole ratios were recorded in order to obtain information about the equilibrium LiBH4 + Al(BH4)3 ⇌ LiAl(BH4)4. This equilibrium is shifted towards the side of the complex LiAl(BH4)4 as the temperature decreases. The compound is more stable in ether solution than in tetrahydrofuran due to the more effective competition of the base tetrahydrofuran for the Lewis acid Al(BH4)3.At high temperature (40°C) a BH4-group exchange dominates, and BH3 cleavage further complicates the investigation in tetrahydrofuran solution.
    Notes: Die Systeme LiBH4/Al(BH4)3/Äther und LiBH4/Al(BH4)3/Tetra-hydrofuran wurden 11B-kernresonanzspektroskopisch bei verschiedener Temperatur, Konzentration und verschiedenen Molverhältnissen untersucht, um Auskunft über die Lage des Gleichgewichts LiBH4 + Al(BH4)3 ⇌ LiAl(BH4)4 zu erhalten. Es zeigte sich, daß sich die Lage dieses Gleichgewichts in Äther mit sinkender Temperatur zu Gunsten des Tetraboranatoalanats verschiebt und daß die Komplexverbindung in Äther stabiler als in Tetrahydrofuran ist. Als Ursache wird die im Vergleich zu Äther groößere Basizität des Tetrahydrofurans angesehen, die erfolgreich mit der Base BH4 um die Lewis-Säure Al(BH4)3 konkurriert.In beiden Lösungsmitteln dominiert bei höherer Temperatur ein Boranatgruppenaustausch. In Tetrahydrofuran gesellt sich die Abspaltung von BH3 hinzu.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 375 (1970), S. 272-280 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: N-Diphenylphosphino-triphenylphosphazene possesses a highly reactive (C6H5)2P group. At room temperature CH3J adds to give (C6H5)3P=N=P(C6H5)2CH 3J whilst phenylbromide did not react under similar conditions. The phosphorous halides (C6H5)2PX(X = Cl, Br)add in a 1:1 mole ratio to yield (C6H5)3P=N=P(C6H5)2—PC6H5)2X; this addition is also the preferred reaction with C6H5PCl2, but PCl3 is in part dehalogenated by (C6H5)3P=N—P(C6H5)2, and PSCl3 desulfurized. The chalcogens O, S, Se, Te readily add to the P(III) atom of the base and this is also the case with BH3. CS2 forms the betaine (C6H5)3 · · P=N—P(C6H5)2—C(S)S. The IR and NMR spectra of the new compounds are discussed.
    Notes: Die reaktive Gruppe im N-Diphenylphosphino-triphenylphosphazen stellt die (C6H5)2P-Gruppe: Methyljodid wird rasch zu (C6H5)3P=N=P(C6H5)2CH3J addiert, (C6H5)2PX (X = CL, Br) zu (C6H5)3P=N=P(C6H5)2X. C6H5PCl2 reagiert ebenfalls noch unter Addition, während PCl3 z. T. enthalogeniert. PSCl3 entschwefelt wird. Die Addition von Boran, Sauerstoff, Schwefel, Selen und Tellur führt zu (C6H5)3(P=N—P(X) · · (C6H5)2 (X = BH3, O, S, Se, Te). CS2 wird zum Betain \documentclass{article}\pagestyle{empty}\begin{document}$({\rm C}_6 {\rm H}_5)_3 {\rm P} = {\rm N} - \mathop {\rm P}\limits^ \oplus ({\rm C}_6 {\rm H}_5)_2.{\rm C}({\rm S})\mathop {\rm S}\limits^ \ominus$\end{document} angelagert. Die IR- und KMR-Spektren der neuen Verbindungen werden diskutiert.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 389 (1972), S. 225-234 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The reaction of CdCl2 or CdBr2with LiBH4, in ether yields no pure Cd(BH4)2, but Li2Cd(BH4)4 was isolated as an oily etherate. Similarly, NaCd(BH4)3 was obtained from CdCl2 and NaBH4 in ether and tetrahydrofurane as solvents. LiCd(BH4)3 and NaCd(BH4)3 were also formed from the components in ether solution. In these solutions Cd migrates to the anode confirming their formulation as tetrahydroborato-cadmates.Cadmiumtetrahydroborate was formed in the reaction of cadmium methoxide with diborane in tetrahydrofurane (THF) and isolated as crystalline solvates. It reacts with pyridine to give Cd(BH4)2 · 3 NC5H5 and with NH3 to yield Cd(NH3)6(BH4)2.
    Notes: Aus CdCl2 oder CdBr2 ließ sich durch Umsetzung mit LiBH4 in Äther kein reines Cd(BH4)2 gewinnen, wohl aber Li2Cd(BH4)4 als ein Ätheratöl, sowie aus der Umsetzung von CdCl2 mit NaBH4 in Äther oder Tetrahydrofuran ein NaCd(BH4)3. LiCd(BH4)3 und NaCd(BH4)3 bilden sich auch aus den Komponenten. Die Wanderungsrichtung des Cadmiums bei Überführungsmessungen belegt die Formulierung als Boranatocadmate.Cadmiumboranat wurde als Tetrahydrofuransolvat bei der Reaktion von Cadmium-methoxid mit Diboran erhalten. Mit Pyridin reagiert es zu Cd(BH4)2 ·3 NC5H5, mit Ammoniak zu [Cd(NH3)6](BH4)2.
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  • 7
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Trimethylamine-alane adds to tetrabutylammonium tetrahydroborate in benzene to yield tetrabutylammonium trimethylamine-tetrahydroborato-trihydroaluminate. The BH4 group of this novel complex hydrido-anion is bound via a single hydrogen bridge to the aluminium atom. Although there is ir-spectroscopic evidence for the formation of a similar tetraphenylphosphonium salt in the reaction of tetraphenylphosphonium tetra-hydroborate and trimethylamine-alane (employed in excess), the products are tetraphenylphosphonium tetrahydroaluminate and trimethylamine-tetrahydroborato-alane. However, tetraphenylarsonium tetrahydroborate yields triphenylarsine and (CH3)3N · AlH2BH4 under similar conditions.Tetrabutylammonium, tetraphenylphosphonium and tetraphenylarsonium tetrahydro-aluminates were prepared from the respective tetrahydroborate and LiAlH4.
    Notes: Trimethylamin-Alan addiert in Benzol 1 Mol Tetrabutylammoniumboranat zu Tetrabutylammonium-trimethylamin-boranato-alanat, in dem die Boranat-gruppe über eine BHAl-Brücke an das Aluminium-Atom gebunden ist. Ein analoges Tetraphenylphosphoniumsalz ist bei der Reaktion zwischen Tetraphenylphosphoniumboranat mit (CH3)3N · AlH3 zwar nachweisbar; die Hauptreaktion (überschuß an Alan) führt aber zu Tetraphenylphosphoniumalanat und (CH3)3N · AlH2BH4. Tetraphenylarsoniumboranat liefert bei der 1:1-Umsetzung mit (CH3)3N · AlH3 Triphenylarsin und (CH3)3N AlH2BH4.Tetrabutylammonium-, Tetraphenylphosphonium- und Tetraphenylarsoniumalanat entstehen aus den entsprechenden Boranaten durch doppelte Umsetzung mit LiAlH4.
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