Amido-derivatives of metals and metalloids. Part XIII. Dialkylamides of low-valent titanium: their preparation and properties

Abstract

Novel dialkylamides of titanium(III) and titanium(II) are reported. Dialkylamides of titanium(III) are prepared by (i) salt elimination (TiCl₃/3LiNR₂; (π-C₅H₅)₂TiCl/LiNR₂); (ii) amine elimination {Ti(NMe₂)₃/C₅H₆ for [π(C₅H₅)Ti(NMe₂)₂]₂}; or (iii) transamination (for mixed dialkylamides). For (i) when R = isopropyl, two chlorines were displaced from TiCl₃; in all other cases total replacement of chlorine was achieved. Dialkylamides of titanium(II) were prepared by the volatility controlled disproportionation: 2Ti^III⇌ Ti^II+ Ti^IV. The structures of the dialkylamides of titanium(III) are of interest because they are amido-bridged and show strong metal–metal interaction.