Preparation and structural study of monocyclopentadienylalkoxoniobium (V) derivates. Crystal structure of {[Nb(η-5-C5H4SiMe3)Cl]2(μ-O)(μ-OOC6H4)2}

Abstract

Alcoholysis with catechol or substitution reactions with NaOPh on Nb(¿5-C5H4R)Cl4 (R = H, SiMe3) have given new alkoxoniobium(V) derivatives of the type Nb(η5-C5H4R)Cl3(OPh) (R = H, SiMe3) Nb(η5-C6H5)Cl2(O2C6H4) and {[Nb(η5-C5H4SiMe3)Cl]2(μ-O)(μ-O2C6H4)2}. The crystal structure of the last species has been studied. The two metal atoms, 3.079(1) Å apart, are symmetrically bridged by the oxo and the two catechol ligands. The two oxygen atoms of each catecholate group are coordinated to the metal atoms, one of them to one Nb atom and the other bridging the two Nb atoms. Chloride and CpSiMe3 ligands complete the coordination sphere of both metal atoms.