Preparation, characterisation, molecular and crystal structure of the octaruthenium arene clusters [Ru8H4(CO)18(η6-arene)](arene = C6H6 or C16H16)

Abstract

Two octaruthenium arene clusters, [Ru₈H₄(CO)₁₈(η-⁶-arene)](arene = C₆H₆1 or C₁₆H₁₆2), have been isolated from the thermolysis of [Ru₃(CO)₁₂] in octane, in the presence of cyclohexene (C₆H₁₀) or [2.2] paracyclophane (C₁₆H₁₆), respectively. Both compounds 1 and 2 have been characterised in the solid state by single-crystal X-ray diffraction and their molecular and crystal structures determined. The reaction of 2 with CO resulted in conversion to the carbido cluster [Ru₆C(CO)₁₄(µ₃-η²:η²:η²-C₁₆H₁₆)] and [Ru₃(CO)₁₂] in quantitative amounts. Compound 1 did not react in the same way but yielded both [Ru₄H₄(CO)₁₂] and [Ru₄H₂(CO)₁₃].