Vinyl homologation via methyl migration to µ-vinyl at a diruthenium centre

Abstract

Treatment of the µ-vinyl cation [Ru₂(CO)(MeCN)(µ-CO)(µ-CHCH₂)(η-C₅H₅)₂]⁺ with Cl^– gives [Ru₂Cl(CO)(µ-CO)(µCHCH₂)(η-C₅H₅)₂], which in turn reacts with LiCuMe₂ at –15°C to afford [Ru₂Me(CO)(µ-CO)(µ-CHCH₂)(η-C₅H₅)₂], structurally characterised by X-ray diffraction; the latter undergoes methyl migration to the α-carbon of the vinyl at room temperature, yielding the isomeric µ-propenyl complexes [Ru₂(µ-H)(CO)₂(µ-CHCHMe)(η-C₅H₅)₂] and [Ru₂(µ-H)(CO)₂(µ-CMeCH₂)(η-C₅H₅)₂].