Electrophilic Addition vs Electron Transfer for the Interaction of Ag + with Molybdenum(II) Hydrides. 2.Reaction with CpMoH(CO) 2 (PMe 3 )
Résumé
The interaction of CpMoH(CO)2(PMe3), 1, with AgBF4 in acetonitrile establishes an equilibrium (K = 9 ± 1) with the hydride-bridged adduct [Cp(CO)2(PMe3)Mo(μ-H)Ag(MeCN)x]BF4, 4, which is in a fast chemical exchange on the NMR time scale with compound 1. The interaction of 1 and AgBF4 in THF leads to the formation of the trinuclear complex {[CpMoH(CO)2(PMe3)]2Ag}BF4, 5, as an insoluble white solid in 73% yield when the Mo/Ag ratio is 2:1. The nature of the precipitate does not depend on the relative stoichiometry of the two reagents. When redissolved in acetonitrile, compound 5 dissociates, generating a mixture of 1 and 4. Compound 4 slowly evolves to the solvent adduct, [CpMo(CO)2(PMe3)(MeCN)]BF4, 3, with elimination of hydrogen gas and metallic silver. The decomposition of 4 could be interpreted as either an inner-sphere electron transfer or a substitution of unstable “AgH”.
Domaines
Chimie de coordinationOrigine | Fichiers produits par l'(les) auteur(s) |
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