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'Phosphonium Ylides' in keywords
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1Author    R. S. Tewari, S. K. Suri, K. C. GuptaRequires cookie*
 Title    Studies on Thiocarbonyl Olefination Reactions with Phosphonium Ylides  
 Abstract    Reactions of several semi-stabilized phosphonium ylides with 2,7-dibromofluorenethione and thiobenzophenone, have been reported to give substituted 9-benzylidene-2,7-dibromo-fluorenes and 1-(substituted phenvl)-2,2-diphenyl ethylenes respectively in fair to good yields. The structural identities were based on spectral data. 
  Reference    Z. Naturforsch. 34b, 606—608 (1979); received November 2 1978 
  Published    1979 
  Keywords    Ylides, Phosphonium Ylides, Thioketones, Olefins 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0606.pdf 
 Identifier    ZNB-1979-34b-0606 
 Volume    34 
2Author    Florian Breitsameter, Peter Mayer, Alfred SchmidpeterRequires cookie*
 Title    Die Kondensation von Ylidylchlorphosphanen mit Phosphanen und Bis(diphenylphosphanyl)methan und -amin The Condensation o f Ylidyl Chlorophosphines with Phosphines and Bis(diphenylphosphino)methane and -amine  
 Abstract    Ylidyl chlorophosphanes 1 and dichlorophosphanes 2 react with trimethylsilyl phosphanes to yield the ylidyl diphosphanes 3, 4,5, 7 and the 2-ylidyl triphosphanes 8. From the reaction of compounds 1 with lithium diphosphanyl amide and diphosphanyl methanide result the ylidyl diphosphonium ylides 11 and ylidyl diphosphinimines 13. The former rearrange to give the ylidyl triphosphanyl methanes 12. The chloromethyl diphosphinimine 13c enters a cyclization to give the 1,2,3,5-azatriphosphole derivative 14, the structure of which has been solved by X-ray analysis. From the reaction of ylidyl bis(chlorophosphanes) 17 and 20 with the same reagents the 1,2,4,5-tetraphosphinine derivative 18 and the 1,2,3,5,6-azatetraphosphinine derivatives 19 and 21 are obtained. 
  Reference    Z. Naturforsch. 55b, 519—526 (2000); eingegangen am 21. Februar 2000 
  Published    2000 
  Keywords    Phosphonium Ylides, Diphosphanes, 1, 2, 3, 5-Azatriphospholes 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0519.pdf 
 Identifier    ZNB-2000-55b-0519 
 Volume    55 
3Author    Hans-Peter Schrödel, Alfred Schmidpeter, Heinrich Nöth#Requires cookie*
 Title    Gerüstumlagerungen bei einem Yliddiylphosphan-Tetrameren Skeletal Rearrangements of an Ylidediylphosphane Tetramer  
 Abstract    Condensation of the bis(trimethylsilyl)ylide Ph3PC(SiMe3)2 with PX3 (X = Cl, Br) yields the ionic tetramers 4a,b of ylidediyl-halophosphanes. Their cations (Ph3PC)4P4X 3+ possess a tetraphosphabicyclo[2.2.2]octane (or tetraphospha-barrelane) skeleton ([AC]3BD spin system in 31P NMR spectra). Reaction of 4a with A1C13 or GaCl3 converts the singly charged cation into the tetracation (Ph3PC)4P44+ having a cubane structure ([ABJ4 spin system in the 3IP NMR spectum). SbCl5 oxidizes 4a to give the dication (Ph3PC)4P4Cl4~+ (counter ion: SbCl52") with the barrelane skeleton either preserved (7) or rearranged into a tetraphospha-bicylco[3.3.01-octane structure 8. In the latter case the dication contains a central diphosphanedionium bridge. Replacement of a chloro-substituent in 4a by an amino group also gives rise to a further dissociation and a concomitant rearrangement. The resulting dications (Ph3PC)4P4NR2Cl2+ possess a tetraphospha-bicyclo-[3.2.1]octane structure (with eight nonequivalent phosphorus atoms). 
  Reference    Z. Naturforsch. 53b, 1285—1293 (1998); eingegangen am 22. Juni 1998 
  Published    1998 
  Keywords    Phosphonium Ylides, Halophosphanes, Chloride Abstraction, Skeletal Rearrangement, Tetraphospha-bicyclooctanes 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-1285.pdf 
 Identifier    ZNB-1998-53b-1285 
 Volume    53 
4Author    H. N. Öth, J. K. NizekRequires cookie*
 Title    Reduktion eines Bis(chlorphenylphosphanyl)methylids zum entsprechenden Diphosphan und Tetraphosphinan  
 Abstract    R e d u ctio n o f a B is(c h lo ro p h en y lp h o sp h an y l)m e th y lid e to the C o rresp o n d in g D ip h o sp h a n e and T etraphosp h in an e F. B reitsam eter, A. S ch m id p e te r* , The bis(phosphanyl)ylides Ph3PC(PPh2)2, Ph3PC(PPhCl)2 (3) and Ph3PC(PCl2)2 have ana­ logous molecular structures. Details reflect the different charge transfer from the ylide center to the phosphanyl substituents. Chlorination destroys the chirality of 3. Reduction leads to the diphosphane 8 and the 1,2,4,5-tetraphosphinane 9 which are also included in the structural comparison. 
  Reference    (Z. Naturforsch. 54b, 1—7 [1999]; eingegangen am 31. August 1998) 
  Published    1999 
  Keywords    Phosphonium Ylides, Negative Hyperconjugation, Phosphorus Carbon Heterocycles, Diphos-phirane, Tetraphosphinane 
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 TEI-XML for    default:Reihe_B/54/ZNB-1999-54b-0001.pdf 
 Identifier    ZNB-1999-54b-0001 
 Volume    54 
5Author    P.Requires cookie*
 Title    Phosphonio-substituierte 1,3-Diphosphanaph thaline aus der a,o-Kondensation von Phosphonium-benzyliden  
 Abstract    h o sp h o n io -S u b stitu te d 1 .3 -D ip h o sp h a n ap h th a le n es from th e a,o -C o n d e n sa tio n o f P h o sp h o n iu m -b en z y lid e s G eo rg Jo ch em , A lfred S chm idpeter* 
  Reference    Z. Naturforsch. 51b, 773—777 (1996); eingegangen am 21. Dezember 1995 
  Published    1996 
  Keywords    Phosphonium Ylides, Electrophilic Aromatic Substitution, 1, 3-Benzodiphosphinines, Spontaneous Chlorophosphine Dissociation, Selective Oxidation by Elemental Sulfur 
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 TEI-XML for    default:Reihe_B/51/ZNB-1996-51b-0773.pdf 
 Identifier    ZNB-1996-51b-0773 
 Volume    51 
6Author    Hans-Peter Schrödel, Alfred SchmidpeterRequires cookie*
 Title    Phosphorandiyl-l,3,5-triphosphinane/ Phosphonio-l,3,5-triphosphinin Kationen Phosphoranediyl-l,3,5-triphosphinanes / Phosphonio-l,3,5-triphosphinine Cations  
 Abstract    Depending on the reaction conditions, the condensation of triphenylphosphonium bis(trimethylsilyl)methylide 1 with phosphorus trichloride and phosphorus tribromide gives the cyclic trimers (Ph3P=CP-X)3, X = Cl, Br, trihalo-tris(triphenylphosphoranediyl)-1,3,5-triphosphinanes 3 and 5. In solution the compounds dissociate to give the ionic forms 4 and 6 which rapidly exchange the halide between the halophosphine and the phosphenium moieties. The exchange is slowed down when the halide ion is replaced by a tosylate ion. Substitution of the covalent chloride of 4 for diphenylphosphino groups gives again an ionic product 10, while the introduction of a morpholino group as well as the replacement of all chloride by triflate give dicationic compounds 12 and 13. Reaction of 3 with gallium trichloride finally leads to the tris(triphenylphosphonio)-l,3,5-triphosphinine trication as a major equilibrium participant. 
  Reference    Z. Naturforsch. 52b, 162—168 (1997); eingegangen am 24. Oktober 1996 
  Published    1997 
  Keywords    Phosphonium Ylides, Halophosphines, Phosphenium Ions, 1, 3, 5-Triphosphinines, Halide Exchange 
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 TEI-XML for    default:Reihe_B/52/ZNB-1997-52b-0162.pdf 
 Identifier    ZNB-1997-52b-0162 
 Volume    52