摘要:
Reaction of Ti{eta(5)-C5H4SiMe2-eta-N(CH2)(2)NRR'}Cl-2 with Nb(eta(5)-C5H4SiMe2Cl)Cl-4 affords the tethered heterodinuclear complexes TiCl2{eta(5)-C5H4SiMe2-eta-N(CH2)(2)-K-NRR'}Nb(eta(5)-C5H4SiMe2-Cl)Cl-4, which are thermally unstable in solution and evolve to render an equimolar mixture of Ti(eta(5)-C5H4SiMe2Cl)Cl-3 and the corresponding cyclopentadienyl-amido niobium compounds, Nb{eta(5)-C5H4SiMe2-eta-N(CH2)(2)NRR'}Cl-3. These compounds are straightforwardly obtained from the reaction of Nb(eta(5)-C5H4SiMe2Cl)Cl-4 with 1 equiv of the appropriate diamine, NH2(CH2),-NRR', in the presence of 2 equiv of NEt3, in high yield. In this reaction, the presence of the functional pendant chain plays a central role not only in determining the course of the reaction but also in stabilizing the final product, from both an electronic and a steric point of view. The molecular structure of Nb{eta(5)-C5H4SiMe2-eta-N(CH2)(3)-eta-NH2]Cl-3 has been determined by X-ray diffraction methods.