1218792-21-2Relevant academic research and scientific papers
Titanium ferrocenyl-phosphinimide complexes
Ramos, Alberto,Stephan, Douglas W.
, p. 1328 - 1338 (2010)
Oxidation of [CpFe(η5-C5H4PtBu 2)] with Me3SiN3 gave the phosphinimine [CpFe(η5-C5H4PtBu2NSiMe 3)] (1) which was used to prepare [Cp′TiCl 2(NPtBu2C5H4)FeCp] (Cp′ = Cp 2, Cp* 4) and subsequently [Cp′TiMe2(NPtBu 2C5H4)FeCp] (Cp′ = Cp 3, Cp* 5). Similarly, [(η5-C5Ph5)Fe(η5- C5H4PtBu2NSiMe3)] 6 was converted to [CpTiX2(NPtBu2C5H4) Fe(η5-C5Ph5)] (X = Cl 7, Me 8). The bis-phosphinimine [Fe{η5-C5H4PtBu 2(NSiMe3)}2] (9) was prepared and used to obtain [{Fe(η5-C5H4PtBu2N) 2}TiCl2] (10) and [{Fe(η5-C 5H4PtBu2N)2}TiMe2] (11). These species exhibited a temperature dependent conformational change in the chelate geometry on the NMR time scale. Cyclic voltammetry studies showed pseudo reversible redox waves assigned to the Fe2+/Fe3+ couple for 2 and 4, while 10 exhibited only irreversible oxidations. Compound 9 was also used to prepare [Fe(η5-C5H4PtBu 2NTiXCl2)2] (X = Cl 12, Cp 13, Cp* 15). Compounds 3 and 5 react with B(C6F5)3 or [CPh3][B(C6F5)3] to generate salts of the formula [Cp′TiMe{(NPtBu2C5H 4)FeCp}]X (Cp′ = Cp, X = [MeB(C6F5) 3] 17a, [B(C6F5)4] 17b; Cp′ = Cp*, X = [MeB(C6F5)3] 18a, [B(C 6F5)4] 18b). Compounds 18 further generated [Cp*TiMe{HNPtBu2(C5H4) Fe(η5,η1-C5H4)}]X (X = [MeB(C6F5)3] 19a, [B(C6F 5)4] 19b), respectively. The cationic species 17a and 18a are very active polymerization catalysts, giving polyethylene with activities of 2400 and 5000 g mmol-1 h-1 atm-1, respectively at 25 °C. The Royal Society of Chemistry 2010.
