1290103-49-9Relevant academic research and scientific papers
Titanium "constrained geometry" complexes with pendant arene groups
Dureen, Meghan A.,Brown, Christopher C.,Morton, Jason G. M.,Stephan, Douglas W.
, p. 2861 - 2867 (2011/05/13)
The synthesis of the proligands C5Me4HSiMe 2N(H)R) (R = CMe2Ph 1, 2-C6H4Ph 2) was accomplished via a straightforward salt metathesis reaction of the appropriate lithium amide and ClSiMe2(C5Me5H). Generation of the dilithio salt and reaction with TiCl3·(THF) 3 followed by oxidation gave C5Me4SiMe 2N(C6H4Ph)TiCl2 (3) in low yield. In contrast, deprotonation of 1 and 2 and reaction with (Me2N) 2TiCl2 afforded C5Me4(SiMe 2NR)Ti(NMe2)2 (R = CMe2Ph 4, 2-C6H4Ph 5), respectively, in good yields Treatment with MeI gave the analogs C5Me4(SiMe2NR)TiI 2 (R = CMe2Ph 6, 2-C6H4Ph 7). Reduction of 7 with potassium graphite afforded C5Me 4(SiMe2NC6H4Ph)Ti 8. Treatment of 6 and 7 with MeMgBr afforded C5Me4(SiMe2NR) TiMe2 (R = CMe2Ph 9, 2-C6H4Ph 10). Complexes 9 and 10 in combination with the activator [Ph3C][B(C 6F5)4] catalyzed the polymerization of styrene and ethylene. Copolymerization was also investigated. While the catalyst derived from 10 showed poor activity, compound 9 showed markedly higher activity than 10 and (C5Me4)SiMe2(NtBu)]TiMe2. The Royal Society of Chemistry 2011.
