Hydrocarbon complexes of iron, ruthenium, and osmium. Part 13. The chemistry of dicarbonyl(trimethylsilyl)(1—3;6—7-η-8-endo-trimethyl-silycyclo-octatrienyl)ruthenium, a pentalene precursor

Abstract

Reactions of [Ru(SiMe₃)(CO)₂{1–3;6–7--C₈H₈(8-endo-SiMe₃)}] with the compounds [Ru(SiMe₃)₂(CO)₄], [Ru₂(SiMe₃)₂(CO)₈], or [Ru₃(CO)₁₂12] give triruthenium pentalene complexes [Ru₃(CO)₈{C₈H_6–n(SiMe₃)_n}](n= 0–2). Also formed are two closely related diruthenium complexes [Ru₂(SiMe₃)(CO)₅(C₈H₈SiMe₃)] and [Ru₂(SiMe₃)(CO)₄(C₈H₈SiMe₃)]; the former contains a cyclic η⁷–C₈ ligand which ring-opens on thermolysis to yield an η⁸–C₈ ligand in the latter. Reactions of [Ru(SiMe₃)(CO)₂{1–3;6–7-η-C₈H₇(SiMe₃)₂–5,8}] with the same reagents give only the pentalene complexes [Ru₃(CO)₈{C₈H_6–n(SiMe₃)_n}](n= 0–3), but in increased yields. Heterodimetallic complexes [FeRu(SiMe₃)(CO)₅(C₈H₈SiMe₃)] and [MnRu(CO)₇(C₈H₇)] are obtained on treating [Ru(SiMe₃)(CO)₂{1–3;6–7-η-C₈H₈(8-endo-SiMe₃)}] with [Fe₂(CO)₉] or [MnMe(CO)₅], respectively.