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  • 1
    ISSN: 0044-2313
    Keywords: Diphosphane(4) ; Diborane(6) ; Borane-tetrahydrofuran ; Diphosphane-borane ; Diphosphane-1,2-bis(borane) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 239. On the Reaction of Diphosphane(4) with Diborane(6) and with THF-Borane: Formation of Diphosphane-borane, P2H4 · BH3, and Diphosphane-1,2-bis(borane), BH3 · P2H4 · BH3Diphosphane(4) always reacts with diborane(6) in the temperature range of -118 to -78°C, to furnish a mixture of diphosphane-borane, P2H4 · BH3 (1), and diphosphane-1,2-bis(borane), BH3 · P2H4 · BH3 (2), in addition to small amounts of triphosphane-1,3-bis(borane), BH3 · P3H5 · BH3, and phosphane-borane, BH3 · PH3, irrespective of the molar ratios of the reactants employed. The formation of the 1 : 1 adduct P2H4 · B2H6 reported in the literature [4] could not be confirmed. The structures of compounds 1 and 2 were investigated by nuclear magnetic resonance spectroscopy which revealed the complete, homolytic cleavage of diborane(6). As a result of the bonding of one BH3 group to diphosphane(4), the Lewis basicity of the other PH2 group is markedly reduced. Similar mixtures of products are obtained when the borane adduct THF · BH3 is employed in an analogous reaction. In the case of a 1 : 1 molar ratio of P2H4 : THF · BH3 at -78°C, the reaction furnishes compound 1 exclusively. This product can be isolated in the pure state and is found to be appreciably more stable than diphosphane(4).
    Notes: Diphosphan(4) reagiert mit Diboran(6) im Temperaturbereich von -118 bis -78°C bei unterschiedlichen Reaktandenverhältnissen stets zu einem Gemisch aus Diphosphan-boran, P2H4 · BH3 (1), und Diphosphan-1,2-bis(boran), BH3 · P2H4 · BH3 (2), mit etwas Triphosphan-1,3-bis(boran), BH3 · P3H5 · BH3, und Phosphan-boran, BH3 · PH3. Die Bildung des in der Literatur beschriebenen 1 : 1-Adduktes P2H4 · B2H6 [4] konnte nicht bestätigt werden. Nach kernresonanzspektroskopischen Strukturuntersuchungen der Verbindungen 1 und 2 findet eine vollständige homolytische Spaltung von Diboran(6) statt. Durch die Bindung einer BH3-Gruppe an Diphosphan(4) wird die Lewis-Basizität der anderen PH2-Gruppe deutlich herabgesetzt. Mit dem Boran-Addukt THF · BH3 entstehen ähnliche Produktgemische. Bei Reaktion im Molverhältnis P2H4 : THF · BH3 = 1 : 1 (-78°C) wird ausschließlich Verbindung 1 gebildet, die rein isolierbar und merklich beständiger als Diphosphan(4) ist.
    Additional Material: 4 Ill.
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  • 2
    ISSN: 0044-2313
    Keywords: Tetraisopropyloctadecaphosphane(4) ; 8,14,16, 18-tetraorganyloctacyclo[13.2.1.02,13.03,11.04,9.05,7.06,10.012,17]octadecaphosphanes ; organylpolycyclophosphanes ; conjuncto-phosphane skeletons ; octacyclo[13.2.1.02,13.03,11.04,9.05,7.06,10.012,17]octadecaphosphane ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 219. Tetraisopropyloctadecaphosphane(4), P18i-Pr4  -  Preparation and Structure Determination by Nuclear Magnetic ResonanceTetraisopropyloctadecaphosphane(4) (1) has been obtained by reaction of i-PrPCl2 with P4 and magnesium and subsequent thermolysis of the crude reaction product, and has been isolated in 95% purity. According to NMR-spectroscopic investigations, 1 contains a conjuncto-phosphane skeleton consisting of a P11(5)- and a P9(3)-structural element analogous to that of deltacyclane, joined through a common P2-bridge. Thus, 1 is 8,14,16, 18-tetraisopropyloctacyclo[13.2.1.02,13.03,11.04,9.05,7.06,10.012,17]octadecaphosphane. Compound 1 is formed as a mixture of two configurational isomers 1 a and 1 b, which differ from each other in their spatial arrangements of the isopropyl group at P8.
    Notes: Tetraisopropyl-octadecaphosphan(4) (1) wurde durch Reaktion von i-PrPCl2, P4 und Magnesium und anschließende Thermolyse des Rohproduktes gewonnen und in 95proz. Reinheit isoliert. Nach kernresonanzspektroskopischen Untersuchungen enthält 1 ein Konjunkto-Phosphangerüst aus einem P11(5)-und einem Deltacyclan-analogen P9(3)-Strukturelement, die eine P2-Brücke gemeinsam haben. Demnach handelt es sich bei 1 um 8,14,16,18-Tetraisopropyl-octacyclo[13.2.1.02,13.03,11.04,9.05,7.0 6,10.012,17]octadecaphosphan. Verbindung 1 entsteht als Gemisch von zwei Konfigurationsisomeren 1a und 1b, die sich in der räumlichen Anordnung der Isopropyl-Gruppe an P8 unterscheiden.
    Additional Material: 2 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 617 (1992), S. 31-36 
    ISSN: 0044-2313
    Keywords: 1,2-Di-tert-butyldiphosphane ; 1,2,3-Tri-tert-butyltriphosphane ; Tetra-tert-butylcyclotetraphosphane ; 1-(tert-Butylphosphino)-2,3,4-tritert-butylcyclotetraphosphane ; 1-(1,2-Di-tert-butyldiphosphino)-2,3,4-tri-tert-butylcyclotetraphosbhane ; tert-Butylpolyphosphanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 224. On the Thermolysis of 1,2-Di-tert-butyldiphosphane, 1,2,3-Tri-tert-butyltriphosphane, and Tetra-tert-butylcyclotetraphosphaneOn disproportionation of 1,2-di-tert-butyldiphosphane, H(t-Bu)P—P(t-Bu)H (1), 1,2,3-tri-tert-butyltriphosphane, H2(t-BuP)3 (2), is formed which reacts further at temperatures above 100°C to give 1-(tert-butylphosphino)-2,3,4-tri-tert-butylcyclotetraphosphan, P5(t-Bu)4H (4). Compound 4 reacts with 1 or 2 with lengthening of the P-sidechain to furnish the corresponding 1-(1,2-di-tert-butyldiphosphino)-2,3,4-tri-tert-butylcyclotetraphosphane, P6(t-Bu)5H (5). At temperatures above 170°C, 5 disproportionates into the tetra-tert-butylcyclotetraphosphane, (t-BuP)4 (3) which is stable up to about 200°C, and the bicyclo[3.1.0]hexaphosphane P6(t-Bu)4 from which the polycyclophosphanes P9(t-Bu)3 and P8(t-Bu)6 arise during the further course of the thermolysis. These products are finally converted through even more phosphorus-rich and more highly condensed t-butylcyclophosphanes into elemental phosphorus. In each reaction step, varying amounts of the monophosphane derivatives t-BuPH2, (t-Bu)2PH, and (t-Bu)3P are formed. The proposed course of the reaction is further substantiated by the pyrolysis products of pure 2 and 3.
    Notes: Bei der Disproportionierung von 1,2-Di-tert-butyldiphosphan, H(t-Bu)P—P(t-Bu)H (1), entsteht 1,2,3-Tri-tert-butyltriphosphan, H2(t-BuP)3 (2), das oberhalb von 100°C zu 1-(tert-Butylphosphino)-2,3,4-tri-tert-butylcyclotetraphosphan, P5(t-Bu)4H (4), weiterreagiert. Verbindung 4 bildet mit 1 oder 2 unter Verlängerung der P-Seitenkette das entsprechende 1-(1,2-Di-tert-butyldiphosphino)-2,3,4-tri-tert-butylcylotetraphospha, P6(t-Bu)5H (5). Bei Temperaturen über 170°C disproportioniert 5 in das bis etwa 200°C beständige Tetra-tert-butylcyclotetraphosphan, (t-BuP)4 (3), und das Bicyclo[3.1.0]hexaphosphan P6(t-Bu)4, aus denen im weiteren Verlauf der Thermolyse die Polycyclophosphane P9(t-Bu)3 und P8(t-Bu)6 entstehen. Diese gehen schließlich über noch phosphorreichere und höherkondensierte tert-Butylcyclophosphane in elementaren Phosphor über. Bei jedem Reaktionsschritt werden wechselnde Mengen der Monophosphanderivate t-BuPH2, (t-Bu)2PH und (t-Bu)3P gebildet. Der angegebene Reaktionsverlauf wird durch die Thermolyseprodukte von reinem 2 und 3 bestätigt.
    Additional Material: 3 Ill.
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  • 4
    ISSN: 0044-2313
    Keywords: Penta-tert-butylundecaphosphane(5) ; 3,5,6,10,11-penta-tert-butyltetracyclo[5.4.0.02,9.04,8]undecaphosphane ; organylpolycyclophosphanes ; configurational isomers of polycyclic phosphanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 213. Penta-tert-butylundecaphosphane(5), P11(t-Bu)5 - Preparation and Structure Determination by Nuclear Magnetic ResonancePenta-tert-butylundecaphosphane(5) (1) has been obtained by reacting t-BuPCl2, PCl3, and magnesium and subsequently thermolysing the crude reaction product, and has been isolated in 85% purity. According to NMR spectroscopic investigations, the structure of 1 differs from that of the undecaphosphanes P11R5 with smaller alkyl groups reported previously [2, 3]. The P11(5) skeleton of 1 is derived from the P9(5) skeleton, which is analogous to brexane [2, 17], by condensation of a -P(t-Bu)-P(t-Bu)- bridge. Thus 1 is 3,5,6,10,11-penta-tert-butyltetracyclo[5.4.0.02,9.04,8]undecaphosphane. Compound 1 is formed as a mixture of two configurational isomers 1a and 1b, which differ from each other in their spatial arrangements of the tert-butyl groups on P10 and P11.
    Notes: Penta-tert-butyl-undecaphosphan(5) (1) wurde durch Reaktion von t-BuPCl2, PCl3 und Magnesium und anschließende Thermolyse des Rohproduktes gewonnen und in 85proz. Reinheit isoliert. Nach kernresonanzspektroskopischen Untersuchungen hat 1 eine andere Struktur als die bereits bekannten Undecaphosphane P11R5 mit kleineren Alkylgruppen [2, 3]. Das P11(5)-Gerüst in 1 leitet sich von dem P9(5)-Gerüst mit Brexan-Struktur [2, 17] durch Anfügen einer -P(t-Bu)-P(t-Bu)-Brücke ab. Demnach handelt es sich bei 1 um 3,5,6,10,11-Penta-tert-butyl-tetracyclo[5.4.0.02,9.04,8]undecaphosphan. Verbindung 1 entsteht als Gemisch von zwei Konfigurationsisomeren 1a und 1b, die sich in der räumlichen Anordnung der tert-Butylgruppen an P10 und P11 unterscheiden.
    Additional Material: 3 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 2042-2047 
    ISSN: 0044-2313
    Keywords: Diphosphane-borane ; Triphosphane-2-borane ; Triphosphane-1,3-bis(borane) ; Sodium-1,1,2-tris(borane)-1,2,2-trihydrogendiphosphide ; Diphosphane(4) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 240. On the Reactive Behaviour of Diphosphane-borane, P2H4 · BH3Under mild temperature conditions, the thermal decomposition of diphosphane-borane (1) gives rise to the formation of phosphane-borane, PH3 · BH3, and triphosphane-2-borane, PH2—PH(BH3)—PH2 (2). In the presence of diphosphane-1,2-bis(borane), triphosphane-1,3-bis(borane), BH3—PH2—PH—PH2—BH3 (3), is formed additionally. The thermolysis product at room temperature is a polymeric solid of varying composition which contains phosphorus, boron, and hydrogen.Compound 1 reacts with metalating agents such as n-BuLi, LiBH4, and NaBH4 to furnish the borane-trihydrogendiphosphide ion, [PH2—PH—BH3]-, which immediately disproportionates to give the corresponding mono-and triphosphane derivatives. In the presence of an excess of THF-borane and in the case of a 1 : 1 molar ratio of 1 : NaBH4, the disproportionation does not occur and the new diphosphide derivative sodium-1,1,2-tris(borane)-1,2,2-trihydrogendiphosphide, Na[(BH3)2PH—PH2BH3] (4) can be obtained. The action of additional NaBH4 yields the diphosphide dianion with four coordinated BH3 groups.
    Notes: Die thermische Zersetzung von Diphosphanboran (1) führt unter milden Temperaturbedingungen zur Bildung von Phosphan-boran, PH3 · BH3, und Triphosphan-2-boran, PH2—PH(BH3)—PH2 (2). In Gegenwart von Diphosphan-1,2-bis(boran) entsteht zusätzlich Triphosphan-1,3-bis-(boran), BH3—PH2—PH—PH2—BH3 (3). Bei Raumtemperatur wird ein polymerer Feststoff gebildet, der Phosphor, Bor und Wasserstoff in wechselnder Zusammensetzung enthält.Die Verbindung 1 reagiert mit Metallierungsmitteln, wie n-BuLi, LiBH4 und NaBH4, zum Boran-trihydrogendiphosphid-Ion, [PH2—PH—BH3]-, das sofort zu entsprechenden Mono- und Triphosphanderivaten disproportioniert. Bei Anwesenheit von überschüssigem THF-Boran und Reaktion im Molverhältnis 1 : NaBH4 = 1 : 1 kann die Disproportionierung verhindert und das neue Diphosphidderivat Natrium-1,1,2-tris-(boran)-1,2,2-trihydrogendiphosphid, Na[(BH3)2PH—PH2BH3] (4), gewonnen werden. Mit weiterem NaBH4 entsteht das Diphosphid-Dianion mit vier koordinierten BH3-Gruppen.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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