ansa-Metallocene derivatives XXI *. Syntheses of etheno-bridged ansa-titanocene derivatives by the McMurry reaction
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چکیده
207 Novel olefin-linked biscylopentadienylligands have been prepared by McMurry coupling reactions of benzoyland acetyl-cyclopentadienyl sodium. Reactions of the disodium salts with TiC1 4 or TiCl 3 • 3THF afford the alkene-bridged ansa-titanocene dichlorides. 13C-NMR shifts of the bridge carbon atoms do not indicate any interaction between the olefin 'IT-system and the metal.
منابع مشابه
ansa - Metallocene derivatives XXIII * .
9 Titanocene and zirconocene complexes with a phenyl or I-naphthyl substituent in one ,B-position of each Cs-ring ligand and with an interannular tetramethylethanoor dimethylsilano-bridge have been prepared. Racemic complex isomers, which are formed together with varying amounts of their meso isomers, were separated from the latter and characterised by lH NMR spectroscopy and X-ray crystallogra...
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