Anionic Cyclopentadienyl C_60 Complexes of Molybdenum and Tungsten; The Strange Case of Iron

摘要

Thermal and photochemical reactions of the carbonylate salts A[eta~5-C_5H_5)Fe(CO)_2], A[(eta~5-C_5H_5)Mo(CO)_3] and A[(eta~5-C_5H_5)W(CO)_3] (A = Na, PPN) in THF with C_60 result in all cases in electron transfer to give [C_60]~- and the transient 17-electron, metal-centered radicals CpFe(CO)_2, CpMo(CO)_3 and CpW(CO)_3, respectively. Subsequent self-coupling of the three metal-centred radicals then results in the formation of the metal-metal bonded dimers [CpFe(CO)_2]_2, [CpMo(CO)_3]_2 and [CpW(CO)_3]_2. In contrast, while the mixture of Na[C_60] and [CpFe(CO)_2]_2 does not react further under p9hotochemical conditions, photolysis of mixtures of Na[C_60] and both [CpMo(CO)_3]_2 and [CopW(CO)_3]_2 ultimately results in com-plete homolysis of the dimers and regeneration of the corres-ponding metal-centered readicals. which then combine with the [C_10]~- remaining in solution to form the eta~2-C_60 complexes A[CpMo(CO)_2(eta~2-C_60] and A[CpW(CO)_2(eta~2-C_60].