C-H Activation and CO2 Insertion Reactivity of Unsolvated Lanthanide Alkyl and Aryl Metallocenes

Event Name/Location

227th National Meeting of the American Chemical Society: Organometallic Metallocenes / Anaheim, California

Presentation Date

3-2004

Document Type

Lecture

Presenters/Authors

Jeremy M. Perotti, University of California, IrvineFollow
Joseph W. Ziller, University of California, Irvine
William J. Evans, University of California, Irvine

Description

Among the most reactive types of organolanthanide complexes are the unsolvated decamethylmetallocene alkyls, [(C₅Me₅)₂LnR]_n. These complexes are difficult to isolate since they typically activate C-H bonds in arene and ethereal solvents. Previous attempts to make these complexes have involved difficult multi-step syntheses. Recently, it has been shown that the readily prepared metallocene cations, [(C₅Me₅)₂Ln][µ-Ph₂BPh₂], are convenient precursors to unsolvated lanthanide methyl metallocenes, such as [(C₅Me₅)₂LnMe]_n (Ln=Sm, Lu), both of which crystallize with asymmetric structures. This has allowed the reaction chemistry of [(C₅Me₅)₂SmMe]₃ to be investigated for the first time. This unsolvated methyl complex metallates toluene to give a material with spectral characteristics appropriate for [(C₅Me₅)₂SmCH₂Ph]_n but derivatization with CO₂ gives a mixture of benzyl and meta tolyl carboxylates. Solid state data on the [(C₅Me₅)₂SmMe]₃/toluene product shows a disordered structure with two metallocenes per tolyl unit. To obtain more information on these basic C-H activation and CO₂ insertion reactions, the reactivity of related [(C₅Me₅)₂SmR]_n complexes was examined. Synthesis of the [(C₅Me₅)₂SmR]_n complexes by both C-H activation starting with [(C₅Me₅)₂SmMe]₃ and ionic metathesis starting with [(C₅Me₅)₂Sm][µ-Ph₂BPh₂] were examined. This manifold of inter-related unsolvated alkyl and aryl metallocene reaction chemistry will be described.

NSUWorks Citation

Perotti, Jeremy M.; Ziller, Joseph W.; and Evans, William J., "C-H Activation and CO2 Insertion Reactivity of Unsolvated Lanthanide Alkyl and Aryl Metallocenes" (2004). Chemistry and Physics Faculty Proceedings, Presentations, Speeches, Lectures. 4.
https://nsuworks.nova.edu/cnso_chemphys_facpres/4