Iv. Shchirinaeingorn et al., OXIDATION OF THE EXO-PHENYLCYCLOHEXADIENYL AND ENDO-PHENYLCYCLOHEXADIENYL IRON COMPLEXES FE(ETA(5)-6-PHC(6)H(6))(ETA(5)-C5H5), Russian chemical bulletin, 45(7), 1996, pp. 1608-1610
The rate of oxidatively induced homolytic scission of the C(sp(3))-H b
onds in the iron phenylcyclohexadienyl complexes Fe(eta(5)-6-PhC(6)H(6
))(eta(5)-C5H5) (1) depends on the spatial orientation of the Ph subst
itutent. In the case of the (1(endo)(+.)) radical cation this process,
resulting in the cationic biphenyl complex [Fe(eta(6)-C6H5C6H5)(eta(5
)-C5H5)] (2(+)), is fast and proceeds for several minutes. in the case
of the more stable radical cation (1(exo)(+.)) the formation of 2(+)
is slow and takes tens minutes to complete.