Amido- and imido-ethylpyridine titanium complexes. Crystal structure of {Ti[NCH2CH2py]Cl2(THF)}2

Compounds of general formula N(R1)(R2)CH2CH2py (py=C5H4N; R1=R2=SiMe3, 1a; R1=H, R2=SitBuMe2, 1b; R1=SiMe3, R2=SitBuMe2, 1c; R1=SiMe3, R2=Ph, 5) were synthesised. They readily reacted with TiCl4 to afford the corresponding amidoaminotrichlorides {Ti[N(R2)(CH2CH2py)]Cl3} (R2=SiMe3, 2a; R2=SitBuMe2, 2b; R2=Ph, 6). The related imido derivatives {Ti[N(CH2CH2py)]Cl2}n (3b) and {Ti[N(CH2CH2py)](L)Cl2}2 (L=THF, 3c; PMe3, 3d) were isolated upon heating and reaction with L, respectively. Reaction of 6 with THF afforded the corresponding adduct, {Ti[N(Ph)(CH2CH2py)](THF)Cl3} (7). Compound 3b reacted with LiNMe2 to give asymmetrical {Ti2[N(CH2CH2py)][N(CH2CH2py)]′Cl4} (4a). Compound {CpTi[N(CH2CH2py)]Cl}n (4b), was formed when 3b reacted with NaCp. Analogous studies with 2a and 6 led to Cp2TiCl2. {Cp2Ti2[μ-N(Ph)]Cl2} (8) was isolated as the product of CpTiCl3 and Na[N(Ph)CH2CH2py]. The molecular structure of 3c was determined by X-ray single crystal diffraction.