SINGLE-SOURCE PRECURSORS OF LEAD TITANATE - SYNTHESIS, MOLECULAR-STRUCTURE AND REACTIVITY OF MU(4)-O)(MU(3)-O-I-PR)(2)(MU-O-I-PR)(4)(O-I-PR)(4)

The reaction between Ti(O-i-Pr)(4) and [Pb(O-i-Pr)(2)](infinity) or Pb 4O(O-i-Pr)(6) offers the mixed-metal oxoalkoxide, mu(4)-O)(mu(3)-O-i-P r)(2)(mu-O-i-Pr)(4)(O-i-Pr)(4) (1) which has been characterized by cry stallography at -120 degrees C. 1 belongs to the monoclinic space grou p P2(1)/n with a 10.286(14) Angstrom, b = 22.564(4) Angstrom, 18.709(5 ) Angstrom, B = 97.93(5), V = 4301(6) Angstrom(3), and Z = 4. Compound 1 represents the first example of a structurally characterized ''sing le-source'' precursor having a Pb:Ti stoichiometry appropriated for Pb TiO3. The 1:1 stoichiometry between the metals is retained by reaction between 1 and acetic acid or acetylacetone (1:2 molar ratio), Pb2Ti2O (OAc)(2)(O-i-Pr)(8) (2) and Pb2Ti2O(acac)(2)(O-i-Pr)(8) (3) being obta ined respectively. All compounds have been isolated in high yields and were characterized by microanalysis, FT-IR and NMR (H-1, C-13, and Pb -207). Hydrolysis-condensation reactions of the various species giving lead titanate have been achieved.