Modified synthesis of Ru–Rh heterobimetallic metallacarboranes based on ruthenium exo-nido complexes and not accompanied by exo-nido → closo rearrangement

The use of improved protocol for the reaction of rhodium acetylacetonate complexes (diene)RhAcac [diene is 1,5-cyclooctadiene or norbornadiene] with exo-nido-ruthenacarboranes 5,6,10-[RuCl(PPh₃)₂]-5,6,10-(μ-H)₃-10-H-7,8-R₂-7,8-C₂B₈H₆ (R = H or Me) allowed us to synthesize three new binuclear complexes, wherein the ruthenium atom preserved exo-position and the rhodium-containing moiety coordinated to the open pentagonal face of exo-nido-complex. In addition, one known bimetallacarborane was also prepared for the evaluation of synthetic efficiency of the new procedure.