Eu(hfc)3 is the metalloorganic compound with the formula . It is a structural analogue of Eufod but contains three heptafluoropropylhydroxymethylenecamphorate anions instead of heptafluoro-tert-butyl pentanedionates. It features an octahedral molecular geometry Eu(III) center. Like Eufod, it is used as a chemical shift reagent (CSR), to increase the dispersion of signals in NMR spectra, exploiting its Lewis acidity and paramagnetism.
Both Eufod and Eu(hfc)3 are chiral, but unlike Eufod, Eu(hfc)3 exists as a single enantiomer owing to chirality of its camphor-derived ligands. Consequently, Eu(hfc)3 forms diastereomeric adduct with chiral Lewis bases. In this way, Eu(hfc)3 can be useful for determining optical purity.
Reactions Eu(hfc)3 forms 1:2 adducts with hard Lewis bases:
This reaction is highly reversible, as required for the complex to serve as a CSR.
Related reagents Europium tris[3-(trifluoromethylhydroxymethylene)-(+)-camphorate] is closely related to Eu(hfc)3 but with .
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