Reaction of the amino-alkoxides HOCH(CH2NMe2)2 (Hbdmap) and HOC(CH2NMe2)3 (Htdmap) with [Ti(OR)4] yields a series of heteroleptic titanium alkoxides [Ti(OR)4−n(L)n] (L = bdmap, tdmap). Substitution of the monodentate alkoxide with the chelating alkoxides becomes progressively more difficult, with homogeneous products being obtained only for n = 1, 2. The structure of [Ti(OEt)3(bdmap)]2, a µ-OEt bridged dimer, has been determined. Hydrolysis of [Ti(OR)2(L)2], by adventitious moisture affords the dimeric oxo-alkoxides [Ti(O)(L)2]2, both of which have been characterised crystallographically. These two compounds have also been prepared by reaction of [Ti(NMe2)2(L)2] with the hydrated metal salts [Zn(acac)2·2H2O] and [Zn(OAc)2·2H2O] using the intrinsic water molecules in these salts to react with the labile amido groups, though the former also produces Me(Me2N)C
C(H)C(O)Me from reaction of liberated HNMe2 with the coordinated acac ligand, while the latter also affords the ligand exchange product [Zn(OAc)(bdmap)]. In neither case does the free dimethylamino group of [Ti(O)(L)2]2 coordinate a second metal. The dimeric structure of [Zn(OAc)(bdmap)]2 has been established, and the structure of the tetrameric oxo-alkoxide [Ti(O)(OPri)(OCH2CH2NMe2)]4 is reported for comparison with others in this study. [Ti(OEt)3(bdmap)]2 has been used as a precursor in AACVD (Aerosol-Assisted Chemical Vapour Deposition) to generate amorphous TiO2 films on glass at 440 °C, and TiO2@C nanoparticles of approximate diameter 350 nm with a carbon coating of width ca. 75 nm on heating in a sealed container at 700 °C.
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