SYNTHESIS AND CHARACTERIZATION OF VOLATILE, THERMALLY STABLE BIS(1,1,1,5,5,5-HEXAFLUOROPENTANE-2,4-DIONATO)BARIUM-POLYETHER, BIS(1,1,1,5,5,5-HEXAFLUOROPENTANE-2,4-DIONATO)STRONTIUM-POLYETHER AND CALCIUM-POLYETHER COMPLEXES, SUITABLE AS PRECURSORS IN CHEMICAL VAPOR-DEPOSITION

Complexes of the type M(hfac)2-polyether, bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato)M-polyether (M = Ba, Sr, polyether = tetraglymc; M = Ba, polyether = hexaglyme; M = Ca, polyether = triglymc), are obtained in high yield upon reaction of M(hfac)2 with one equivalent of polyether. The complexes thus obtained appear to be sublimable, non-hygroscopic, thermally stable solids. They have been characterized by elemental analysis, molecular weight determinations, NMR spectroscopy, mass spectrometry, IR and TG-DTA analysis. The complex Ba(hfac)2-tetraglymc has been characterized by an X-ray structure determination. The barium atom is found to be coordinated by all nine oxygen atoms, with the polyether ligand wrapped around barium in a plane, with one hfac ligand on top of this plane and another below. The absence of short intermolecular interactions explains why the compound sublimes easily without decomposition.