The Synthesis of Organometallic Ylides Interaction of Methylenetriphenylphosphorane with Bis(^5-cyclopentadienyl)- zirconium and -hafnium Dichlorides and the Molecular Structure of Bis(^5-Cyclopentadienyl)chlorozirconylmethylenetriphenylphosphorane
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چکیده
Dedicated to Prof. Dr. h. c. H. Behrens on his 65th birthday The interaction of (^-CsHsfeMC^ (M = Zr, Hf) with excess CH2-PPh3 in THF gives (??5-C5H5)2MCl(CH-PPh3) as yellow orange needles. Nuclear magnetic resonance spectra show hindered rotation about the P-C bond with = 8.6 kcal/mole for M = Zr and 8.3 kcal/mole for M — Hf, respectively. The X-ray molecular structure of the zirconium complex shows a relatively short Zr-C bond length of 2.152 A and a long P-C bond length of 1.716 A.
منابع مشابه
Amineborane dehydrogenation promoted by isolable zirconium sandwich, titanium sandwich and N(2) complexes.
Catalytic dehydrogenation of R(2)NHBH(3) (R = Me, H) promoted by a family of bis(cyclopentadienyl)titanium and bis(indenyl)zirconium compounds is reported; structure-reactivity relationships as a function of cyclopentadienyl and indenyl substituents have been examined.
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