Substituents effect on molecular structures of 13-vertex closo-metallacarboranes of rare earths. Synthesis and structural characterization of metallacarboranes bearing nido- and arachno-carborane ligands

Several new 13-vertex closo-metallacarboranes of rare earths incorporating nido- and arachno-carborane ligands have been prepared and structurally characterized. They represent a new class of metallacarboranes bearing a η7-carboranyl ligand recently discovered in our laboratory. This work indicates that the substituents on carborane cage carbons may affect the overall molecular structures of the resultant 13-vertex closo-metallacarborane complexes, but have little influence on the interactions between the central metal ion and nido- or arachno-carborane ligand.