INTERACTION BETWEEN COBALTOCENIUM AND DECAMETHYLCOBALTOCENIUM SALTS AND PH(3)ELI (E=SI, GE, SN)

Reactions of cobaltocenium salts [(C(5)R(5))(2)Co]PF6 (R = H, Me) with Ph(3)ELi (E = Si, Ge, Sn) and with Ph(2)SbLi mainly follow two pathwa ys (nucleophilic addition and one-electron reduction), yielding cobalt cyclopentadiene-cyclopentadienyl complexes (eta(4)-Ph(3)EC(5)R(5))(et a(5)-C(5)R(5))Co (R = H, E = Si, Ge, Sn; R = Me, E = Si) and cobaltoce nes (C(5)R(5))(2)Co (R = H, Me), respectively. The contribution of nuc leophilic addition of Ph(3)ELi decreases in the order of elements Si > Ge > Sn and when hydrogen atoms are replaced by methyl groups in the initial cobaltocenium salt. Thermal decomposition of cobalt cyclopenta diene-cyclopentadienyl complexes results in substituted cobaltocenes.