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1988 (1)
1Author    Franjo Gol, Gerd Hasselkuß, PeterC. Knüppel, Othmar StelzerRequires cookie*
 Title    Lineare Oligophosphaalkane, XX [1] Alkalimetall-und Trimethylsilylderivate PH-funktioneller Methylenbisphosphane Linear Oligophosphaalkanes, XX [1] Alkali Metal and Trimethylsilyl Derivatives of PH-Functional Methylenebisphosphanes  
 Abstract    The synthesis of the trimethylsilyl derivatives of the PH-functional methylenebisphosphanes, R 2 ^"(Me 3 Si)"P—CH 2 —PR(SiMe 3) (R = Me. /Pr. tBu. Ph. 2.4.6-Me 3 C (,H 2 ; n = 0. 1) is reported. In the Li-phosphides R 2 _"Li"P — CH 2 — PUR used as reactive intermediates, a monomer-oligomer association equilibrium causes a rapid Li-exchange as indicated by the solvent and temperature dependent ^PI'H} and 7 Li NMR spectrum of (/Pr) 2 P-CH 2 -P(/Pr)Li in various solvents (Et : 0. THF and MTHF) in the temperature range from 30 to -110 °C. For the syntheses of the Me-and Ph-substituted PH-functional methylenebisphosphanes R 2 P-CH 2 -PRH and RHP-CH 2 -PRH (R = Me, Ph) the chlorophosphane CKP —CH 2 —PC1 2 is used as a starting material. Bifunctional substituents (Ph —N—N —Ph and Me —N—CO —N—Me) are employed for the first time as protect-ing groups to block one or two PCl-functions in C1T—CIL—PCI-,. Cleavage of the PN-bonds in the five membered ring systems RP-CH 2 -PR-N(Ph)-N (Ph) (R = Me. Ph) with HCl affords the P-substituted methylenebis-chlorophosphanes RC1P—CH 2 — PC1R in satisfactory yields. The compounds have been characterized by 'H. I3 C{ 'H} and 3! F*{'H}NMR spectroscopy. With-in homologous substitution series of methylenebisphosphanes, e.g. R 2 P—CH 2 —PR 2 _"H" the coupling constants 2 /(PP) seem to reflect conformational changes at the PCP-skeleton. 
  Reference    (Z. Naturforsch. 43b, 31—44 [1988]; eingegangen am 15. Juni 1987) 
  Published    1988 
  Keywords    Functional Methylenebisphosphanes Bifunctional Protecting Groups, Lithium and Trimethylsilyl Derivatives, Dynamic Li-Exchange, NMR Spectra 
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 TEI-XML for    default:Reihe_B/43/ZNB-1988-43b-0031.pdf 
 Identifier    ZNB-1988-43b-0031 
 Volume    43