224637-89-2Relevant academic research and scientific papers
Amide-silyl ligand exchanges and equilibria among group 4 amide and silyl complexes
Cai, Hu,Yu, Xianghua,Chen, Shujian,Qiu, He,Guzei, Ilia A.,Xue, Zi-Ling
, p. 8071 - 8078 (2008/10/09)
M(NMe2)4 (M = Zr, 1a; Hf, 1b) and the silyl anion (SiButPh2)- (2) in Li(THF)2SiBu tPh2 (2-Li) were found to undergo a ligand exchange to give [M(NMe2)3(SiButPh2) 2]- (M = Zr, 3a; Hf, 3b) and [M(NMe2) 5]- (M = Zr, 4a; Hf, 4b) in THF. The reaction is reversible, leading to equilibria: 2 1a (or 1b) + 2 2 ? 3a (or 3b) + 4a (or 4b). In toluene, the reaction of 1a with 2 yields [(Me2N) 3Zr(SiButPh2)2] -[Zr(NMe2)5Li2(THF) 4]+ (5) as an ionic pair. The silyl anion 2 selectively attacks the -N(SiMe3)2 ligand in (Me2N) 3Zr-N(SiMe3)2 (6a) to give 3a and [N(SiMe 3)2]- (7) in reversible reaction: 6a + 2 2 ? 3a + 7. The following equilibria have also been observed and studied: 2M(NMe2)4 (1a; 1b) + [Si(SiMe3) 3]- (8) ? (Me2N)3M-Si(SiMe 3)3 (M = Zr, 9a; Hf, 9b) + [M(NMe2) 5]- (M = Zr, 4a; Hf, 4b); 6a (or 6b) + 8 ? 9a (or 9b) + [N(SiMe3)2]- (7). The current study represents rare, direct observations of reversible amide-silyl exchanges and their equilibria. Crystal structures of 5, (Me2N)3Hf- Si(SiMe3)3 (9b), and [Hf(NMe2) 4]2 (dimer of 1b), as well as the preparation of (Me 2N)3M-N(SiMe3)2 (6a; 6b) are also reported.
Unusual Equilibria Involving Group 4 Amides, Silyl Complexes, and Silyl Anions via Ligand Exchange Reactions
Yu, Xianghua,Cai, Hu,Guzei, Ilia A.,Xue, Ziling
, p. 4472 - 4473 (2007/10/03)
Silyl anion SiButPh2- (2) was found to substitute an amide ligand in Zr(NMe2)4 (3) to give the disilyl complex Zr(NMe2)3(SiButPh2)2- (
