Monocyclopentadienyl alkyl alkylidene niobium(V) and tantalum(V) complexes. X-ray crystal-structure of Ta(η5-CP')(CH2SiMe3)2(CHSiMe3)

Abstract

Reactions of monocyclopentadienyl complexes M(η5-Cp′)Cl4 with trimethylsilylmethyl lithium leads to the formation of alkylidene derivatives M(η5-Cp′)(CH2SiMe3)2(CHSiMe3), where M = Nb (1); Ta (2); Cp′= C5Me5 and M = Ta; Cp′ Me3Si(C5H4) (3), 1,3-(Me3Si)2(C5H3) (4). The new complexes were characterized by 1H and 13C NMR spectroscopy and the molecular structure of 2 was studied by X-ray diffraction methods.