摘要:
The reaction of [PhC(NSiMe3)(2)]Li(TMEDA) with TaF5 yields complex 1, [PhC(NSiMe3)(2)](2)TaF3, in 40% isolated yield. The solid-state structure of 1 shows a pentagonal, bipyramidal coordination geometry. Variable temperature F-19-NMR experiments reveal one singlet at an ambient temperature; decoalescence to two singlets (1:2 integration) is observed at - 20 degrees C. Complex 1 reacts with Me2Mg to produce [PhC(NSiMe3)(2)](2)TaMe3 (2). The reaction of 1 with Ph2Mg yields [PhC(NSiMe3)(2)](2)TaF2Ph (3) and [PhC(NSiMe3)(2)](2)TaFPh2 (4). Characterization of 4 by X-ray crystallography shows a ligand arrangement similar to that of 1. (C) 2000 Elsevier Science S.A. All rights reserved.