Sodium β-Diketonate Glyme Adducts as Precursors for Fluoride Phases: Synthesis, Characterization and Functional Validation

Very few sodium complexes are available as precursors for the syntheses of sodium-based nanostructured materials. Herein, the diglyme, triglyme, and tetraglyme (CH3O(CH2CH2O)(n)CH3, n = 2-4) adducts of sodium hexafluoroacetylacetonate were synthesized in a single-step reaction and characterized by IR spectroscopy, H-1, and C-13 NMR. Single-crystal X-ray diffraction studies provide evidence of the formation of the ionic oligomeric structure [Na-4(hfa)(6)](2-)center dot 2[Na(diglyme(2)](+) when the diglyme is coordinated, while a mononuclear seven-coordinated complex Na(hfa)center dot tetraglyme is formed with the tetraglyme. Reaction with the monoglyme (CH3OCH2CH2OCH3) does not occur, and the unadducted polymeric structure [Na(hfa)](n) forms, while the triglyme gives rise to a liquid adduct, Na(hfa)center dot triglyme center dot H2O. Thermal analysis data reveal great potentialities for their applications as precursors in metalorganic chemical vapor deposition (MOCVD) and sol-gel processes. As a proof-of-concept, the Na(hfa)center dot tetraglyme adduct was successfully applied to both the low-pressure MOCVD and the sol-gel/spin-coating synthesis of NaF films.