A New Class of Metallacarboranes: Synthesis and Molecular Structure of the First Example of an Organolanthanide Compound Bearing an η7-Carboranyl Ligand

The first organolanthanide compound containing an η 7 -carboranyl ligand, [{[ η 5: η 7 -Me 2 C(C 5 H 4 )(C 2 B 10 H 11 )]Er} 2 {Na 4 (THF) 9 }] n ( 3 ), has been achieved by treatment of [η 5 -Me 2 C(C 5 H 4 )(C 2 B 10 H 11 )]ErCl 2 (THF) 3 ( 1 ) or [ η 5: η 6 -Me 2 C(C 5 H 4 )(C 2 B 10 H 11 )]Er(THF) 2 ( 2 ) with excess Na metal in THF. The Na + ions in 3 can be replaced by Er 3+ ions, giving the novel tetranuclear cluster [{ η 5: η 7 -Me 2 C(C 5 H 4 )(C 2 B 10 H 11 )}Er 2 ( μ -Cl)(THF) 3 ] 2 ( 4 ).