Synthesis and characterization of some triosmium and triruthenium cluster complexes containing unusual ferrocenyl moieties
Creators: name: Zheng, Tu C.
Publisher: name: University of British Columbia
Year: 2008

description: Series of ferrocenyl ligands, predominantly phosphines, have been prepared: PFcPh2 (Fc=(r15-05H4), Fe(n5-05H5)), PFc2Ph, PEt2Fc, PEtFc2, PFciPrz,PnBuFcPh, PtBu2Fc, Fc'PPh (Fc'4n5-05H4)2Fe), Fc'(PPh2 )2, Fc'(PiPr2 )2pAsFc2Ph, FC(SPh)2, Fc.(SMe)2, SFcPh, Fc2S2, and SbFc3, and characterized by spectroscopic and analytical techniques. The reactions of most of the ferrocenyl phosphine ligands with M3(CO)12 (M=Os, Ru) were studied and a series of complexes of general formulae M3(C0)1 IL, M3(CO)1 01,2, Ru3(CO)9L3, M3(C0)10(L-L), Ru3(CO)9(L-L)L' were prepared and characterized by spectroscopic and analytical techniques. The disubstituted compounds M3(C0)10L2 were found to exist as symmetrical and unsymmetrical isomers. The electronic effects accounting for this phenomenon are discussed. The structure of the unsymmetrical isomer of 0s3(C0)10(PFc2Ph)2 (I) was determined. A large number of pyrolytic reactions of these complexes and/or pyrolytic reactions of M3(C0)12 (M=Os or Ru) with an appropriate ligand were studied in order to prepare metal cluster complexes containing unusual ferrocenyl moieties. These pyrolytic reactions mentioned above have afforded many interesting complexes containing two to five metal atoms with the most common one being three metal atoms. Over a hundred complexes, many of them novel, have been prepared and characterized by spectroscopic and analytical techniques. Over thirty of these have been structurally characterized by using X-ray crystallography, and over thirty await analysis. The novel ferrocyne and ferrodicyne complexes (II) and (III) have been prepared via the pyrolysis of 0s3(C0)11(PFc2Ph) and 0s3(C0)10[Fe(PiPr2)2] respectively and structurally characterized. Four series of complexes (IV), (V), (VI), and (VII) containing Fe (ferrocene)-M (Os or Ru) bonds have been characterized. Series (IV) and (V) show Fe-Os bond distances from 2.813(1) to 2.858(1) A. Some other novel complexes include the first cluster naphthyne complex (VIII), the first 11.3-711,111,116 bonded benzyne complex (VIV), complex (X) resulting from a CO insertion into anOs-R bond, complex (XI) derived from Ph2S, complex (XII) obtained via i-Pr and Fc C-H oxidative addition reactions, and complex (XIII) containing a11-111,715 bonded C5H4 moiety that is derived from a ferrocenyl group. Detailed reaction sequences have been proposed for the pyrolyses of M3(C0)10[Fe(PiPr2 )21 (M=Os, Ru), 0s3(C0)11(PFc2Ph), 0s3(C0)1 (PFciPr2), and0s3(C0)11(PEt2Fc). In addition to a common Fe-M bonding involvement, ferrocenyl groups have been found to undergo orthometalation, hetero-annular metalation, or both, and these reactions are more facile than alkylC-H bond activation of ethyl and i-propyl groups. Ethyl and n-butyl groups undergo a C-H activation only, while i-propyl groups undergo 13 C-Hactivation preferentially. Phenyl and ferrocenyl groups undergo C-P cleavages with the elimination of benzene and ferrocene, i-propyl groups are lost as propene. In conclusion, this study has demonstrated that phosphine ligands on Rua and 0s3 clusters are not inert to further reactions, and this reactivity has been used successfully to prepare a large number of unprecedented type of complexes.