350620-33-6Relevant academic research and scientific papers
A versatile synthetic route for cyclopentadienyl-amido titanium(IV) compounds. NMR spectroscopy study and X-ray molecular structure of [Ti{η5-C5H4SiMe2 NMe(CH2)2-η-NMe}Cl2]
Jiménez, Gerardo,Rodríguez, Esteban,Gómez-Sal, Pilar,Royo, Pascual,Cuenca, Tomás,Galakhov, Mikhail
, p. 2459 - 2467 (2001)
The reaction of the chlorosilyl-substituted cyclopentadienyltitanium compound [Ti(η5-C5H4-SiMe2Cl) Cl3] with N,N′-dimethylethylenediamine in the presence of 2 equiv of NEt3 gave a mixture of two complexes, [Ti{η5-C5H4SiMe2 NMe(CH2)2-η-NMe}Cl2] (1) and [Ti{η5-C5H4SiMe2-η-N(CH 2)2-η-NHMe}Cl2] (2), in a molar ratio of 3:1. However, a similar reaction with N-methylethylenediamine afforded complex 2 regiospecifically. The dialkyl derivatives [Ti-{η5-C5H4SiMe2 NMe(CH2)2-η-NMe}R2] (R = Me (3), CH2Ph (4)) were prepared by reacting the dichloride complex 1 with 2 equiv of MgClMe or 1 equiv of Mg(CH2Ph)2·2THF, respectively. The analogous reaction with LiNMe2 afforded the diamido derivative [Ti{η5-C5H4SiMe2 NMe(CH2)2-η-NMe}(NMe2)2] (5) in high yield. Complex 1 reacts with dry CO2 via insertion of a molecule of CO2 into each of the Ti-N and Si-N bonds to yield the dicarbamate compound [Ti{(η5-C5H4SiMe2OC(O) NMe(CH2)2NMe (η2-CO2)} Cl2] (6), in which the carbamate groups are bound in η2- and η1-fashion. Thermal decomposition of complex 6 afforded the known oxo derivatives [Ti{μ-(η5-C5H4SiMe2-η-O)} Cl2]2 and [(TiCl2)2(μ-O)-[μ-{(η5-C5 H4SiMe2)2-(μ-O)}] with elimination of CO2 and 1,3-dimethyl-2-imidazolidinone. The conformational interconversion of 1 and 6 and the reversible coordination of the terminal NHMe group to the metal center in 2 were studied in solution by DNMR spectroscopy. The crystal structure of 1 was determined by X-ray diffraction methods.
