[Me2Si] ansa bridged complexes of permethyltitanocene: Synthesis and structural characterization of fulvene derivatives with trialkylidenemethane character

Journal of the Chemical Society - Dalton Transactions

Volumn , Issue 9, 1999, Pages 1365-1368

  Lee, Hyosun ^a   Bonanno, Jeffrey B ^a   Hascall, Tony ^a   Cordaro, Joseph ^a   Hahn, Juliet M ^a   Parkin, Gerard ^a  

^a Columbia University ^*  (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 33749100561     PISSN: 03009246     EISSN: None     Source Type: Journal    
DOI: 10.1039/a900173e     Document Type: Article

References (36)

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6. 2 with PhLi.
7. H. Lee, J. Cordaro and J. B. Bonanno, unpublished work.
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17. For a review of bonding in fulvene complexes, see: J. A. Bandy, V. S. B. Mtetwa, K. Prout, J. C. Green, C. E. Davies, M. L. H. Green, N. J. Hazel, A. Izquierdo and J. J. Martin-Polo, J. Chem. Soc., Dalton Trans., 1985, 2037.
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20. Thus, the Ti-C12 bond deviates by only 2.5° from the Ti-centroid vector.
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23. 14b suggests that they may also be considered to possess trialkylidenemethane character.
24. 3H.
25. C. McDade, J. C. Green and J. E. Bercaw, Organometallics, 1982, 1, 1629.
26. ‡ = -2.9(7) e.u. (ref. 17).
27. 2) (5.1 at 80°C). See ref. 7(c).
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31. -1]. The value for the methyl derivative is that determined by the activation parameters listed in ref. 18.
32. 1 is the ring carbon attached to silicon.
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34. 2TiCl, providing further evidence for enhanced electrophilicity of the ansa titanocene system. See ref. 3.
35. It should, however, be noted that computational studies suggest that ring slippage and tilt introduced by incorporation of bulky substituents are not the principal factors responsible for modification of the electron density at a metal center in a series of non-bridged titanocene complexes; rather the changes in electron density merely reflect the inductive effects of the various substituents. See: B. E. Bursten, M. R. Callstrom, C. A. Jolly, L. A. Paquette, M. R. Sivik, R. S. Tucker and C. A. Wartchow, Organometallics, 1994, 13, 127.
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