文档介绍：Decamethylsilicocene: Synthesis,
Structure, Bonding and Chemistry
THORSTEN KU¨ HLER and PETER JUTZI
Faculty of Chemistry, University of Bielefeld,
Universita¨tsstraße 25, D-33615 Bielefeld, Germany
I. Introduction ................................... 1
II. Synthesis and Structure of Decamethylsilicocene ............... 3
III. Bonding in Decamethylsilicocene . . . ..................... 7
IV. Chemistry of Decamethylsilicocene (1) ..................... 9
A. Attempts to Prepare the Radical Cation and the Radical Anion of 1 . . 9
B. Reduction of Geminal and Vicinal pounds ....... 10
C. Insertion into Non-polar and into Polar Bonds
(X–X, H–X, El–Hal, El–C) ......................... 11
D. Reaction with Me5C5BCl2, BHal3,B2Cl4, AlHal3, and Me5C5AlCl2 ... 17
E. Reaction with HBF4 Á OEt2 ......................... 20
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F. Formation and Characterization of the (Me5C5)2SiH Cation ...... 21
G. Reaction with Chalcogene-Atom Sources ................. 22
H. Cycloaddition Reactions: Stable Products, Reactive Intermediates
and Alternative Pathways . ......................... 24
I. Formation of the Cluster SiAl14(C5Me5)6 ................. 30
J. Adduct Formation with CO and N2 .................... 31
V. Conclusions and Perspectives .......................... 31
Acknowledgements ................................ 32
References ..................................... 32
I
INTRODUCTION
The metallocene era started with the synthesis of ferrocene and with the
right description of the structure and bonding of Only a
few years after this epochal discovery, the first metallocenes of the group 14
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elements tin and lead were synthesized, namely stannocene, (H5C5)2Sn, and
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plumbocene (H5C5)2Pb; the analogous pound germano-
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cene, (H5C5)2Ge, was prepared nearly two decades later.
Some years later, the introduction of the pentamethylcyclopentadienyl
ligand into the plex chemistry of the group 14 elements has allowed
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the syn