Synthesis and Reaction of Neutral and Cationic Alkyltantalum Complexes with a Linked Cyclopentadienyl-Carboranyl Ligand

A trimethyltantalum complex with a Cp-carboranyl ligand was prepared via a salt metathesis reaction of TaCl2Me3 with [Li2{C5H4CMe2(C2B10H10)}(OEt2)2]. Two equivalents of carbodiimides reacted with Ta(Cp-carboranyl)Me3 to form four-membered azametallacyclic compounds with an exocyclic imine group. A Lewis base stabilized cationic species was generated by the reaction of Ta(Cp-carboranyl)Me3 with B(C6F5)3(THF).