Metal-cyclopentadienyl complex

Verdet and Stille1 employed brominated poly(phenylene oxide) intermediates in an effort to synthesize more stable catalyst supports containing (cyclopentadienyl)metal complexes. Treatment of poly(oxy-2,6-dimethyl-l,4-phenylene) with N-bromosuccinimide under photolytic conditions produced only the bromomethyl derivative if the D.F. did not exceed 0.35. Subsequent treatment of the bromomethylated polymer with sodium cyclopentadienide afforded the cyclopentadienyl functionalized polymer, 5, but the reaction was accompanied by crosslinking and it was not possible to remove the bromomethyl substituents quantitatively. 

The suffix ocene is formally reserved for bis(t]-cyclopentadienyl) metal complexes. The name uranocene does not fit this convention, but has been used as a trivial name in the literature. 

Bent bis(cyclopentadienyl)metal complexes have been of interest for several years. In the initial theoretical model Ballhausen and Dahl (16) proposed... 

The traditional names ferrocene, manganocene, ruthenocene, nickelocene, etc. are given to the respective bis(ri5-cyclopentadienyl)metal complexes. Ocene names should not be coined for isoelectronic species such as chromocene for bis(ri6-benzene)chromium, for structurally analogous... 

The strategies used to synthesize metal complexes with the cyclopentadienyl ligands portrayed in Scheme 13 are briefly described below. The most widely used procedure begins with the corresponding cyclopentadiene derivative, which can be transformed into a cyclopentadienyl metal complex by a variety of metallation methods as described in... 

Hurley AL, Maddox MP III, Scott TL, Flood MR, Mohler DL. Photoinduced DNA cleavage by cyclopentadienyl metal complexes conjugated to DNA recognition elements. Org Lett 2001 3 2761-4. 

Unlike the compounds obtained with the heavier halogens, polyfluori-nated metallocene derivatives cannot be prepared from the permercurated metallocenes. Thermally stable pentafluorinated ruthenocenes have been made from the (oxocyclohexadienyl)(cyclopentadienyl)metal complexes by flash vacuum pyrolysis (Scheme 6).53 54 Decafluorometallocenes, [M(C5F5)2], are still unknown potential routes to these compounds starting from fluorinated cyclopentadiene (C5F5H)55 or from the decachlorometal-locenes48 have been unsuccessful. However, there seems to be no fundamental steric or electronic barrier to their eventual preparation. 

III. Synthetic Methods for Bulky Cyclopentadienyl Metal Complexes.. .. 310... 

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