Hexafluoroisopropoxides of divalent and trivalent lanthanides. Structures and luminescence properties

The reactions of amides Ln[N(SiMe3)2]3 with hexafluoroisopropanol (CF3)2CHOH gave the corresponding alkoxides Ln[OCH(CF3)2]3 (Ln = Ce (1), Gd (2), Tm (3)). The X-ray diffraction study showed that cerium and thulium isopropoxides have dimeric structures. The reactions of europium(II) and ytterbium(II) iodides with the potassium salt of hexafluoroisopropanol afford complexes of the composition Ln3[OCH(CF3)2]7 (Ln = Eu (4), Yb (5)) containing Ln2+ and Ln3+ cations. The synthesized alkoxides do not exhibit luminescence properties, except for europium isopropoxide 4. The latter compound shows photoluminescence in an acetonitrile solution as a band with a maximum at 330 nm assigned to the 4f65d1 → 4f7 electron transition in divalent europium.