632353-58-3Relevant academic research and scientific papers
Titanium and zirconium chloro, oxo and alkyl derivatives containing silyl-cyclopentadienyl ligands. Synthesis and characterisation
Buitrago, Olga,Jiménez, Gerardo,Cuenca, Tomás
, p. 70 - 76 (2003)
The reaction of the tetramethylcyclopentadiene-silyl substituted derivative C5Me4(SiMe3) (SiMe2Cl) with MCl4 afforded the trichloro mono-tetramethylcyclopentadienyl complexes M(η5 -C5Me4 SiMe2Cl)Cl3 [M=Ti (1), Zr (2)] with selective elimination of SiMe3Cl. Compound 1 reacts with deoxygenated water in methylene chloride, with the evolution of HCl, to give the dinuclear titanium compound {Ti[μ-(η5-C5Me4SiMe2 O-κO)]Cl2}2 (3), which was converted into the μ-oxo complex {Ti[μ-(η5-C5Me4 SiMe2O-κO)]Cl}2(μ-O) (4) by a further hydrolysis reaction which occurred when a solution of 3 in toluene was refluxed for a long period of time in the air. Depending on the size of the alkyl ligand, reactions of the mononuclear compound 1 with an appropriate alkylating reagent rendered the peralkylated Ti(η5-C5Me4SiMe2R) R3 [R=Me (5), CH2Ph (6)] or partially alkylated {Ti[(η5-C5Me4SiMe2 (CH2SiMe3)]Cl(CH2SiMe3) 2} (7) compounds by a salt metathesis route. Attempts to synthesise a partially methylated or benzylated complex were unsuccessful. Treatment of the dinuclear compound 3 with four equivalents of MgClMe yielded the tetramethyl derivative {Ti[μ-(η5- C 5Me4SiMe2O-κO)]Me2} 2 (8), while the same reaction carried out with MgCl(CH2Ph) or Mg(CH2Ph)2·2THF gave the chloro-benzyl derivative {Ti[μ-(η5 -C5Me4SiMe2O-κO)]Cl (CH2Ph)}2 (9) as an equimolar mixture of diastereomers, regardless of the molar ratio of the alkylating reagent used. All of the new compounds were characterised by elemental analysis and NMR spectroscopy.
