Thenoyltrifluoroacetone complexes structures

Similar to the Sr example, lanthanide extraction into ILs has been reported to yield different structures than when prepared with an organic solvent instead the IL. In ILs, the formation of anionic Nd(tta)4 or Eu(tta)4 (Htta = 2-thenoyltrifluoroacetone) complexes with no water coordinated to the metal center is preferred. In nonpolar organic solvents, hydrated, neutral complexes, M(tta)3(H20)M (n = 2 or 3) form [162],... 

Figure 2.21 Structure of the lanthanide complexes [L (tta)3L2] (a) and [L (bta)3L2] (b). Ln represents a trivalent lanthanide ion, tta is 2-thenoyltrifluoroacetonate, bta is benzoyltrifluoroacetonate, and L is a Schiff base...

Several quite stable complexes can be formed with Cf(iii) (see Table 11.9). Complexes of diketones and aminopolycarboxylic acids are considerably more stable than those of tartrate, lactate, oxalate, etc. In some cases, adduct chelates can be formed with Cf (iii), as with californium thenoyltrifluoroacetone chelate and methyl isobutyl ketone (Cf(TTA)3 + MIBK- Cf(TTA) MIBK or Cf(TTA)3 -2MIBK) [23]. With the monodentate ligand tributyl phosphate, the extractable californium adduct from nitric acid solution has been assigned as the 1 3 species Cf(N03)3 3TBP [227]. Quaternary ammonium bases and alkylpyro-catechols (i.e. 4-(a,a -dioctylethyl)pyrocatechol) can form complexes in alkaline solutions [228]. One recent extraction study has examined the influence of the extractant s structure on the extraction behavior of californium [229]. A large number of materials have been investigated for forming extractable complexes of californium and the reader is referred to reviews on the subject [27, 32, 33]. 

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