Cluster and polynuclear compounds. Tetrakis-{(?6-1-isopropyl-4-methylbenzene)ruthenium(II)tetraoxomolybdate(VI)}

The synthesis of (?6-p-MeC6H4Pr-i)4Ru4Mo4O16, a neutral organoruthenium oxomolybdenum cluster that exists as two structural isomers in soln., one of which can be crystd. from dichloromethane/toluene, is described. In the cryst. state, the mol. contains an unprecedented Ru4Mo4O12 framework, which can be described as a central Mo4O4 cube with four folded ORuO flaps resembling the sails of a windmill. In soln., the windmill structure was found to isomerize to a triple-cubane structure; the equil. was dependent on the nature of the solvent. In chloroform, both isomers are present in a nearly 1:1 ratio, while in dichloromethane the triple-cubane isomer is predominant. [on SciFinder(R)]