Reactions of dodecacarbonyl-triangulo-triruthenium and dodecacarbonyltetrahydridotetraruthenium with mixtures of cyclic polyolefins

Abstract

The title complexes react with cyclopentadiene–cycloheptatriene, cyclopentadiene–cyclo-octatetraene, or cycloheptatriene–cyclo-octatetraene mixtures to yield the structurally related fluoxional complexes [Ru₃(CO)₆(η-C₅H₅)-(η-C₇H₇)], [Ru₃(CO)₆(η-C₅H₅)(η⁷-C₈H₉)], [Ru₃(CO)₆(η-C₇H₇)(η⁵-C₈H₉)], and [Ru₃(CO)₆(η⁵-C₈H₉)(η⁷-C₈H₉)]. Each product has one hydrocarbon ligand η⁵-co-ordinated to one ruthenium of a Ru₃ triangle, with the other bridging the remaining two rutheniums in an η⁷ mode. Other products of these reactions include [Ru₄(CO)₇-(η-C₇H₇)₂] and [Ru₃H(CO)₄(η-C₇H₇)(η-C₈H₈)] which contain fluxional bridging cycloheptatrienyl and cyclo-octatetraene rings. The [Ru₃(CO)₆(η⁵-L)(η⁷-L′)](L = C₅H₅ or C₇H₇; L′= C₇H₇ or C₈H₉) complexes are smoothly cleaved by iodine to give [Rul(CO)₂(η⁵-L)] and [Ru₂l(CO)₄(η⁷-L′)].