Synthesis and characterisation of hexa- and hepta-ruthenium carbido carbonyl clusters containing arenes derived from 1,1-diphenylethene

Abstract

The three ruthenium arene clusters [Ru₆C(CO)₁₄(η⁶-PhCHMePh)] 1, [Ru₆C(CO)₁₄(η⁶-PhCCH₂Ph)] 2 and [Ru₇C(CO)₁₄(µ₃-κ∶η⁶∶η⁶-C₆H₄CH₂C₆H₄)] 3 have been synthesized by reaction of 1,1-diphenylethene with triruthenium dodecacarbonyl in octane under reflux. Compound 1 is a 1,1-diphenylethene hexaruthenium carbido cluster (Ru₆C) derivative wherein the organo-group, hydrogenated at the olefinic centre, is bound to the cluster by a single phenyl ring in an η⁶ manner. Compound 2 is a similar Ru₆C derivative wherein the 1,1-diphenylethene ligand remains unsaturated, whilst the third, and minor, product is the first example of a metal carbonyl cluster chelated by a diphenyl ligand and is one of the few examples of an Ru₇C ‘spiked’ octahedron. The subtle electronic effects of the Ru₆C co-ordination in 2 have been probed by ¹H NMR spectroscopy. The solid-state structures of both the hydrogenated derivative 1 and the Ru₇C ‘spiked’ octahedral cluster 3 have been determined by single-crystal X-ray analysis. The supramolecular architecture of 3 has been examined in depth.