STANDARD ENTHALPIES OF FORMATION AND METAL-LIGAND BOND-DISSOCIATION ENTHALPIES OF SOME LEAD(II) BETA-DIKETONATES

The standard enthalpies of formation of some lead(II) beta-diketonates : Pb(aa)(2); Pb(dpm)(2); Pb(zis)(2); Pb(pta)(2); and Pb(hfa)(2) (where aa = pentane-2,4-dionate, dpm = 2,2,6,6-tetramethylheptane-3,5-dionat e, zis = 2-methoxy-2,6,6-trimethylheptane-3,5-dionate, pta = 1,I,1-tri fluoro-5,5-dimethylhexane-2,4-dionate and hfa = 1,1,1,6,6,6-hexafluoro pentane-2,4-dionate) were determined by solution-reaction calorimetry measurements. The corresponding sublimation enthalpies of the complexe s were derived from measurements of saturated vapour pressure by means of the how method. The homolytic (DHR)(Pb-O) and heterolytic (DHI)(Pb -O) bond dissociation enthalpies were hence derived. (C) 1997 Elsevier Science B.V.