VOLATILE ADDUCTS OF RARE-EARTH PIVALOYLTRIFLUOROACETONATES AND HEXAFLUOROACETYLACETONATES WITH HEXAMETHYLPHOSPHORIC TRIAMIDE

The syntheses of the previously unknown complexes Er(PTFA)3.HMPA (I), Nd(PTFA)3.HMPA (II), Er(HFA)3.2HMPA (III), and Nd(HFA) (IV) [PTFA is 1 ,1,1-trifluoro-5,5-dimethylhexane-2,4-dionato (pivaloyltrifluoroaceton ato) ligand, HFA is 1,1,1,2,5,5-hexafluoropentane-2,4-dionato (hexaflu oroacetylacetonato) ligand, and HMPA is hexamethylphosphoric triamide] are reported. The IR spectra prove the coordination of beta-diketonat e anion and HMPA, including the complexes in the vapor phase. The elec tronic absorption spectra of toluene solutions of the complexes I and II give evidence of the coordination of the second HMPA molecule on ad ding the free ligand. The temperature dependences of saturated vapor p ressure of the compounds obtained have been determined by the flow tec hnique. The TGA study has shown that the complexes I and II exhibit hi gh thermal stability and are vaporized on heating in an air stream.