Hydrocarbon complexes of ruthenium. Part II. Reactions of organosilyl- and -germyl-(carbonyl)ruthenium complexes with cyclo-octatrienes

Abstract

An isomeric mixture of cyclo-octa-1,3,5- and -1,3,6-trienes reacts with [Ru(SiMe₃)₂(CO)₄] and with [Ru(SiMe₃)(CO)₄]₂ to give the non-silicon-containing complexes [Ru₂(CO)₆(C₈H₁₀)] and [Ru(CO)₃(C₈H₁₀)] as major products, as well as the tetrahydropentalenyl complex [Ru(SiMe₃)(CO)₂(C₈H₉)]. The germanium analogues [Ru(GeMe₃)₂(CO)₄] and [Ru(GeMe₃)(CO)₄]₂, however, undergo Ge–Ru bond cleavage less readily in reactions with the C₈H₁₀ mixture, and the tetrahydropentalenyl compound [Ru₂(GeMe₃)(µ-GeMe₂)₂(CO)₄(C₈H₉)] is the predominant product. The two complexes [Ru₂(CO)₆(C₈H₁₀)] and [Ru(CO)₃(C₈H₁₀)] are readily prepared from dodecacarbonyltriruthenium and the isomeric mixture of cyclo-octatrienes. The fluxional behaviour of [Ru₂(CO)₆(C₈H₁₀)] has been studied.