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  • 1
    ISSN: 1520-6041
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 259-263 
    ISSN: 0009-2940
    Keywords: Hydrophosphorylation ; Phosphines, alkenyl- ; Phosphines, allenyl- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contribution to the Synthesis and Structural chemistry of some Alkenyl- and Allenylphosphines1,3-Diphenylpropyne, obtained through an improved synthesis, undergoes base-catalyzed hydrophosphorylation with Ph2PH to give 2-(diphenylphosphino)-1,3-diphenyl-1-propene (1). The structure of 1 has been established by single-crystal X-ray diffraction. Regioisomeric 1-(diphenylphosphino)-1,3-diphenyl-1-propene (2) is a minor byproduct of the reaction. Metallation of 1 with n-BuLi followed by treatment with Ph2PCl yields (R,S)-2,3-bis(diphenylphosphino)-1,3-diphenyl-1-propene (3). Methylation of 1 with MeI gives the phosphonium salt 4. Double lithiation of PhCH2C≡CPh and reaction of the intermediate with two equivalents of Ph2PCl affords 1,3-bis(diphenylphosphino)-1,3-diphenylallene (5). This bisterminal phosphino-functionalized allene is converted into an oxide, sulfide, or selenide (5a-c) with the appropriate oxidant. Dephosphorylation of 5 with n-BuLi and subsequent hydrolysis lead to 1-(diphenylphosphino)-1,3-diphenylallene (6). Hydrophosphorylation of 5 with Ph2PH gives 3 by an alternative route.
    Notes: Durch basenkatalysierte Hydrophosphorylierung von 1,3-Diphenylpropin mit Ph2PH wird 2-(Diphenylphosphino)-1,3-diphenyl-1-propen (1) erhalten, dessen Stereochemie durch Röntgenstrukturanalyse aufgeklärt wurde. Als Nebenprodukt werden auch geringe Mengen des regioisomeren 1-(Diphenylphosphino)-1,3-diphenyl-1-propens (2) isoliert. Deprotonierung von 1 mit n-BuLi und nachfolgende Umsetzung mit Chlordiphenylphosphan liefert das doppelt-phosphorylierte Produkt (R,S)-2,3-Bis(diphenylphosphino)-1,3—diphenyl-1-propen (3). Durch Methylierung von 1 läßt sich das entsprechende Phosphoniumsalz 4 darstellen. Ebenfalls ausgehend von 1,3-Diphenylpropin wird nach doppelter Lithiierung, gefolgt von der Umsetzung mit Chlordiphenylphosphan, das erste 1,3′Diphosphino-substituierte Allen 5 synthetisiert. Aus diesem läßt sich durch starke Basen (RLi) eine Phosphinogruppe abspalten, wobei das Monophosphinoallen 6 entsteht. Oxidation sowie Addition von Schwefel und Selen ergeben die zugehörigen Dichalkogenide 5a-c, Hydrophosphorylierung von 5 führt auf einem anderen Weg zu 3.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 1403-1412 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Structure, and Some Reactions of Tris- and Tetrakis(diphenylphosphino)allenesTreatment of the reagent 2, obtained from 1-(diphenylphosphino)-1-propyne (1) and n-BuLi, with Ph2PCl gives high yields of tetrakis(diphenylphosphino)allene (3). On oxidation with H2O2 or Me3SiOOSiMe3, this compound yields the tetraoxide 4a, while with sulfur or selenium the tetrachalcogenides 4b,c are obtained. The allene group is not affected in these processes. In the reaction of 3 with MeLi P - C cleavage occurs to give Ph2PMe and 1,3,3-tris(diphenylphosphino)allenyllithium (5), which is converted into tris(diphenylphosphino)allene (Ph2P)2C=C=CHPPh2 (6) upon hydrolysis. Quaternization with MeI under mild conditions leads to the monoquaternary salts 7 and 8 from 3 and 6, respectively. With excess MeI at higher temperature a phosphonioalkynyl-semiylide salt [(MePh2P)2C-C≡C-PPh2Me]2+ 2 I- (9) is formed from both 3 and 6. The by-product of the P-C cleavage in 3 by MeI is Ph2PMe2+ I-3. - The structures of the allenes 3 and 6 and of the salt 9 have been confirmed by single crystal X-ray diffraction. The Ph2P groups in 3 adopt a similar conformation as found previously for (Ph2P)2C=CH2, with an opposite orientation of the lone pairs of electrons at phosphorus relative to the allene axis. In 6 a rotamer with an approximately symmetrical (“anti”) orientation of the geminal Ph2P groups is present. 9 is found to be another example of semiylidic quaternary salts with a delocalized ylide function.
    Notes: Das aus 1-(Diphenylphosphino)-1-propin (1) mit n-BuLi erhältliche Reagens Ph2P-C≡C-CH2Li(2) ergibt bei der Behandlung mit Ph2PCl hohe Ausbeuten an Tetrakis(diphenylphosphino)allen (3). Diese Verbindung liefert nach Oxidation mit H2O2 oder Me3SiOOSiMe3 das Tetraoxid 4a, mit Schwefel oder Selen die entsprechenden Tetrachalkogenide 4b,c. Die Allengruppierung wird dabei nicht angegriffen. Durch Umsetzung von 3 mit MeLi kommt es zur Spaltung einer P-C-Bindung. Das neben Ph2PMe gebildete 1,3,3-Tris(diphenylphosphino)allenyllithium (5) kann durch Hydrolyse in (Ph2P)2C=C=CHPPh2 (6) verwandelt werden. Bei schonender Quartärisierung mit MeI entstehen aus 3 und 6 die Monoquartärsalze 7 und 8, mit überschüssigem Reagens bei erhöhter Temperatur dagegen als gemeinsames Produkt das Phosphonioalkinyl-semiylid-Salz [(MePh2P)2C-C≡C-PPh2-Me]2+ 2 I- (9). Nebenprodukt der auch hierbei in 3 eintretenden P-C-Spaltung ist Ph2PMe2+ I-3. - Die Strukturen der Allene 3 und 6 sowie des Salzes 9 wurden durch Röntgenbeugungsanalysen an Einkristallen gesichert. Die Ph2P-Gruppen in 3 besitzen ähnliche Konformationen wie im analogen (Ph2P)2C=CH2 mit jeweils entgegengesetzten Orientierungen der freien Elektronenpaare an den P-Atomen zur Allen-Achse. In 6 ist ein Rotameres mit annähernd symmetrischer (“anti”) Orientierung der geminalen Ph2P-Gruppen vorhanden. 9 ist ein weiteres Beispiel für Semiylid-Quartärsalze mit delokalisierter Ylid-Funktion.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 2015-2022 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese and Structures of Simple Mono- ad Bis(phosphino)allenesMetalation of 1,1-dimethylallene with alkyllithium compounds and treatment of the resulting lithiated products with chlorodiphenylphosphane affords 3,3-dimethyl-1-(diphenylphosphino)allene and -1,1-bis(diphenylphosphino)allene (3 and 8, respectively). The success of the syntheses depends strongly on the reaction conditions. With a change in stoichiometry, temperature, or reaction times, isomeric alkynes (CH3)2CH—C≡C—P(C6H5)2 and (C6H5)2P(CH3)2C—C≡CH (6 and 7, respectively) are also obtained, and even substitution of phenyl for alkyl groups at the phosphorus atom may occur. Thus the reaction of the intermediate 6 with tert-butyllithium followed by treatment with (C6H5)2PCl leads to the allene (CH3)2C=C=C[P(C6H5)C(CH3)3][P(C6H5)2] (12). Through the new preparative methods, mono- and (geminally) bis(phosphino)-substituted allenes have now become easily available in good yields. The prototypes 8 and 12 have been structurally characterized by X-ray diffraction analyses. The molecular conformations are very similar to those of analogous geminal di(phosphino)alkenes.
    Notes: 1,1-Dimethylallen kann durch Metallierung mit Alkyllithium-Verbindungen und Umsetzung mit Chlordiphenylphosphan in 3,3-Dimethyl-1-(diphenylphosphino)allen (3) und -1,1-bis(diphenylphosphino)allen (8) übergeführt werden. Der Erfolg der Synthesen hängt stark von den Reaktionsbedingungen ab. Bei abgeänderten Stöchiometrien, Temperaturen und Reaktionszeiten werden auch isomere Alkine (CH3)2CH—C≡C—P(C6H5)2 oder (C6H5)2P(CH3)2C—C≡CH (6 bzw. 7) erhalten, oder es kommt sogar zur Substitution von Phenylresten am Phosphoratom. So wird bei der Einwirkung von tert-Butyllithium auf intermediär gebildetes 6, gefolgt von Metallierung und Umsetzung mit (C6H5)2PCl das Allen (CH3)2C=C=C[P(C6H5)C(CH3)3][P(C6H5)2] (12) gebildet. Über die genannten Verfahren sind damit erstmals einfach und geminal-doppelt phosphinosubstituierte Allene in guten Ausbeuten zugänglich. Die Prototypen 8 und 12 wurden durch Röntgenbeugungsanalysen strukturell charakterisiert. Die gefundenen Konformationen entsprechen weitgehend denen analoger geminaler Di(phosphino)alkene.
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  • 5
    ISSN: 0009-2940
    Keywords: Ferrocenes ; Cyclopentadienes, disilyl- ; Silatropic rearrangement ; Lithium cyclopentadienides ; Metallocene, trinuclear, mixed-metal ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The tetrahydro-4,4,8,8-tetramethyl-4,8-disila-s-indacenyl anion (LH) reacts with or without cyclopentadienyl anion (Cp-) and Fe2Cl4(THF)3 to give the mixed ferrocenes CpFe(LH) and (LH)2Fe in 50 and 63% yield, respectively. Near room temperature and in solution CpFe(LH) exists as a pair of enantiomers (syn-3a/b). According to an X-ray analysis both enantiomers are present in a single crystal. Compound 3 consists of a ferrocene linked to a cyclopentadiene by two Me2Si groups such that the acidic Cp proton points towards the iron. Temperature-dependent NMR spectra show that syn-3a and syn-3b are non-rigid molecules which are interconverted by 1,2-silatropic bond shifts (Ea = 49.2 ± 2.9 kJmol-1). Three more isomers (anti-3a, anti-3b, and the spiro derivative 3c), though present only in low concentration, are engaged in the rearrangement. (LH)2Fe is also non-rigid and exists as a pair of diastereomers (4a and 4b). The isomers of 3 and 4 undergo hydrolysis (e.g., syn-3a/3b gives [(Me2SiOSiMe2)Cp]FeCp (5) among others) and deprotonation. The latter yields CpFe(L-) (7) and (L-)2Fe (8), which are characterized by NMR spectroscopy. 7 forms crystals with [Li(TMEDA)]+ as counterion, and an X-ray analysis shows that lithium and iron are located at opposite sides of the strongly folded ligand L. The reaction of 7 with CrCl2(THF) gives the trinuclear stacked metallocene 9 in 47% yield. 9 has two unpaired electrons which are located essentially in the center of the molecule.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1241-1245 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ambidentate Poly(diphenylphosphino)ethanes and -ethenesBase-catalyzed hydrophosphorylation of CH2=C(PPh2)2 (1) using Ph2PH affords 1,1,2-tris(diphenylphosphino)ethane (2) in high yield. This product is converted into the trisulfide 3 when treated with sulfur, and into a monoquaternary salt 4, when treated with Mel. The onium center appears at one of the two geminal phosphine groups. Treatment of 4 with KH in tetrahydrofuran yields the corresponding ylide 5 as an unstable product. Excess MeI reagent causes P—C cleavage in 1 or 4, but only [MePh2PCH2CH2PPh2Me]I2 (6) was identified among several products. - Base-catalyzed addition of Ph2PH to Ph2PC≡CPPh2 affords tris-(diphenylphosphino)ethene (7) whose molecular structure has been determined by X-ray crystallography. The conformation is similar to that in the reference compounds 1 and cis-Ph2P—CH=CH—PPh2. Judged from its only minor distortions, the C=C unit in 7 is not severely affected by either steric or electronic effects of the Ph2P groups. The hydrophosphorylation of Ph2PC≡CPPh2 with Ph2PH yields yellow 1,2,3,4-tetrakis(diphenylphosphino)-1,3-butadiene (8) as a by-product.
    Notes: Durch basenkatalysierte Hydrophosphorylierung mit Ph2PH wurde CH2=C(PPh2)2 (1) in 1,1,2-Tris(diphenylphosphino)ethan (2) übergeführt. Aus diesem Produkt entsteht mit Schwefel ein Trisulfid 3 und mit MeI ein Monoquartärsalz 4, in dem die Oniumfunktion an einem der geminal substituierten P-Atome auftritt. 4 kann mit KH in THF in das instabile korrespondierende Ylid 5 umgewandelt werden. Überschüssiges MeI reagiert mit 2 oder 4 unter P-C-Spaltung zu mehreren Produkten, unter denen nur [MePh2PCH2CH2PPh2Me]I2 (6) identifiziert wurde. - Die ebenfalls basenkatalysierte Addition von Ph2PH an Ph2-PC≡CPPh2 ergibt Tris(diphenylphosphino)ethen (7), dessen Molekülstruktur röntgenographisch bestimmt wurde. Die Konformation entspricht der in den Vergleichsverbindungen 1 und cis-Ph2P—CH=CH—PPh2. Nach den geringen Deformationen beurteilt, wird die C=C-Einheit in 7 offenbar weder durch sterische noch durch elektronische Effekte nennenswert belastet. Nebenprodukt der Hydrophosphorylierung von Ph2PC≡CPPh2 mit Ph2PH ist das gelbe 1,2,3,4-Tetrakis(diphenylphosphino)-1,3-butadien (8).
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1345-1348 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Gold(I) Complexes of a Geminal Bis(phosphino)allene1,1-Bis(diphenylphosphino)-3-methyl-1,2-butadiene (1) reacts with one or two equivalents of carbonyl(chloro)gold(I) to give - with evolution of CO - the corresponding 1:1 and 1:2 complexes (2, 3), respectively. The crystal structure determination of the 1:1 complex revealed the presence of two crystallographically independent, centrosymmetrical dimers, in which the two gold atoms have a transannular distance of 3.070(1) and 3.002(1) Å, respectively. The coordination of the chlorine atoms leads to a T-shaped coordination array at the gold atoms.
    Notes: 1,1-Bis(diphenylphosphino)-3-methyl-1,2-butadien (1) kann mit einem oder zwei Äquivalenten Carbonyl(chloro)gold(I) unter CO-Entwicklung zu den entsprechenden 1:1- und 1:2-Komplexen (2, 3) umgesetzt werden. Die Kristallstrukturuntersuchung am 1:1-Komplex weist das Vorliegen von zwei kristallographisch unabhängigen, zentrosymmetrischen Dimeren nach, in denen die beiden Goldatome einen transannularen Abstand von 3.070(1) bzw. 3.002(1) Å haben. Die Chloratome sind so gebunden, daß an den Goldatomen eine T-förmige Koordinationsgeometrie entsteht.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1373-1375 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: cis- 1,2-Diphenylcyclopropane; Molecular Structure and Attempted Chelate Complexation of Gallium (I)In an attempt to design a chelating bis(arene) ligand for metals in an s2 electron configuration, the synthesis of cis-1,2-diphenylcyclopropane (1) from ω-benzylideneacetophenone and hydrazine hydrate (followed by pyrolysis) has been optimized. The crystal structure of 1 has been determined by X-ray diffraction [orthorhombic, space group P212121, a = 5.823(1), b = 11.962(2), c = 15.727(3) Å, Z = 4]. The molecules have the expected geometry and dimensions and appear to be ideally suited for complexation of cations like Ga+, as judged from the geometries encountered with non-chelating bis(arene) complexes. 71Ga-NMR spectra of solutions of equimolar quantities of 1 and Ga[GaX4] (X = Cl, Br) in benzene indeed indicate the presence of complexes with monoalkylated arenes, but no crystalline products could be isolated.
    Notes: Im Zuge von Bemühungen um einen Bis(aren)-Liganden, der in der Lage ist, s2-konfigurierte Metalle zu chelatisieren, wurde die Synthese von cis-1,2-Diphenylcyclopropan (1) aus ω-Benzylidenacetophenon und Hydrazin mit nachfolgender Pyrolyse optimiert und die Kristallstruktur dieses Kohlenwasserstoffs bestimmt [orthorhombisch, Raumgruppe P212121, a = 5.823(1), b = 11.962(2), c = 15.727(3) Å, Z = 4]. Die Moleküle besitzen die erwartete Geometrie mit den im voraus abgeschätzten Dimensionen und sollten speziell für die Chelatisierung von Ga(I) geeignet sein. 71Ga-NMR-Daten von Lösungen äquimolarer Mengen 1 und Ga[GaX4], X = Cl, Br, in Benzol zeigen in der Tat die erwartete Komplexbildung an monoalkylierte Aromaten an, es konnten aber keine kristallinen Produkte isoliert werden.
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 70 (1987), S. 1905-1910 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2,3-Bis(diphenylphosphino)-1,3-butadieneA method for synthesis of the title compound is described, using the readily available 2,3-bis(diphenylphosphinoyl)-1,3-butadiene (1) as the starting material. For the protection of the diene system, 1 is first converted into the 1,4-dibromo- and 1,4-dichloro derivatives 2a and b, respectively, by addition of Br2 or Cl2, respectively. The structure of 2b has been determined by single-crystal X-ray diffraction. The molecule has a centrosymmetrical (E)-configuration. Reduction of the phosphinoyl groups by HSiCl3(to give the bis(diphenylphosphino)compound 3), followed by removal of the Cl-atoms using Zn powder, affords the bis(diphenylphosphino)butadiene 4. Compounds 3 and 4 give quaternary phosphonium salts 5 and 6, respectively, on addition of CH3OSO2F or CH3I. The sulfur analogue of 1 is formed on treatment of 4 with elemental sulfur.
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  • 10
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
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