Silane, cyclopentadienyl derivatives

Dialkylbis(cyclopentadienyl)silanes can be used in a similar manner, as in the following preparation of a titanium derivative (R = Me) (96) ... 

Three classes of hybrid HPA are known to be stable to hydrolysis 1. Organometallic derivatives of the type RM (M = Si, Ge, Sn, Pb and R = alkyl or aryl). 2. Cyclopentadienyl-titaninm derivatives. 3. Zirconium alkoxide or phosphate derivatives, all of which are illustrated in Figure 2. We have tested phenyl model compounds of all of these for stability by boiling them in 6M HCl or H2O2 solution. This study showed that only PhP-O-HPA moieties are stable under conditions likely to be encountered in a fuel cell. Never the less we continue to study model compounds of the type RSi-O-HPA due to the large diversity of available ethoxy- and chloro- silanes. 

Inverted names are used only for derivatives of silanes (as Silane, dihromo- and Disilane, hexachloro-), germanes, phosphine, and the like, and as duplicate entries for metal alkyls and aryls, for example. Sodium, cyclopentadienyl-in addition to Cyclopentadienylsodium, but not for the few organic compounds. For the nomenclature of some of these and other classes of compounds, see the heading Nomenclature. 

The preparation of a phosphinocyclopentadiene containing an intervening silane bridge has been reported by Schore/ This wqrk has involved not only the preparation of the usual ferrocenyl derivatives and their subsequent complexation, but a novel zirconium(IV)-iron(0) complex (Figure 7.21). Since cyclopentadienyl zirconium halides represent precursors to useful synthetic reagents, this work represents a significant step towards the assembly of heterobimetallic complexes which contain two reactive metal ions. 

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