OXIDATION OF IENYLCYCLOHEXADIENYL)(ETA(5)-CYCLOPENTADIENYL)IRON BY TRITYL HEXAFLUOROPHOSPHATE

Oxidation of the cyclohexadienyl complex Fe(eta(5)-C5H5)(1-5-eta(5)-6- exo-C5H5-C6H6) (2) by (Ph3C)PF6 (CH2Cl2, from similar to 30 to +20 deg rees C) occurs as two concurrent processes: elimination of an H atom f rom the cyclohexadienyl ligand and replacement of an H atom in the cyc lopentadienyl ring by a CPh3 fragment. A mixture of cationic complexes [Fe(eta(5)-(CH5)-H-5)(eta(6)-Ph-C5H5](+) (1(+)) and [Fe(eta(5)-C5H4CP h3)(eta(6)-Ph-C5H5)](+) (4(+)) with PF6- anions is obtained. Deprotona tion of the mixture of 1(+) and 4(+) complexes under the action of (Bu OK)-O-t in m-xylene followed by boiling of the reaction mixture gives phenylferrocene (7) as the product of eta(6):eta(5)-interring haptotro pic rearrangement.