Ternary adduct

Ternary Adduct Formation Constants of Early Actinide Ions with some Beta-Diketones... 

For the enantiometric [SSS-Yb.la]3+ ternary adducts, A()AAX) gives the open structure whereas X(SSSS) gives the more pocket-like structure. 

Parker reported the very promising behavior of two ligands 67 and 68 [86]. Their Eu and Tb complexes are reported to form complexes with (S)-lactate with up to 4.5 orders of magnitude higher stability than with (R)-lactate in aqueous collidine/HCl buffer, pH 7.4. Recently, structural and NMR investigation of the ternary adducts of 20 a-amino acids and selected peptides with the Yb complex of ligand 69 [87] have been studied. 

The extracting species such as those shown in Eqs. (14) and (15) are mixed quaternary adducts and they can be visualised as forming from the ternary adduct, MAn yB, by replacing the betadiketonate anion by the anion present in the aqueous medium. Alternatively they can be formed by replacing the anion from the adduct ML mB by the betadiketonate anion. It was suggested3,21) that complexes can also be formed in non-aqueous solvents by stepwise replacement of one ligand by another. 

Most of the studies involving HA-B combinations were conducted employing such aqueous media, the extraction from which involves the formation of simple ternary adducts MAn yB and their study can easily be carried out with any of the methods given here. But when quartemary adducts or ion-pairs are involved in the extraction it becomes very difficult to establish their stoichiometry by any single method and very often different types of experimental data need be obtained to confirm such species. 

This method has been widely used where simple ternary adducts are the species responsible for synergism. 

The extraction of some trivalent actinide ions by HPMBP-B mixtures was reported143"145. The extraction constants obtained for different diluents143 are given in Table 19. The constants were shown to decrease with increasing dielectric constant of the diluent. An additional mixed adduct, M(N03)(PMBP)2 2 TOPO participation was also considered when the neutral donor used was TOPO. The involvement of two ternary adducts in these systems was reported in the subsequent work144,145 and the equilibrium constant data are given in Table 20. 

Synthesis, characterization and crystal structure of deuterium-labelled ternary adduct [Ni(CDfiN)g](SbFg)2... 

Binary, ternary, and quaternary adducts refer to the association of two, three, or four different entities, respectively. A monoadduct is a 1 1 association of two different entities and a bisadduct is a 2 1 combination. However, there does not appear to be a systematic method of referring to higher-order adducts (e.g., a 1 2 3 association of three different entities A, B, and C). The term ternary adduct does not adeqnately reflect the relative ratios of A, B, and C and any combination of mono-, bis-, and tris- is awkward at best. Indeed, such an adduct could just be referred to as a 1 2 3 adduct of A, B, and C. Adducts can also be referred to as dimers, trimers, tetramers, and so on (i.e., n-mers). However, an adduct usually refers to an association in which at least two entities are different, whereas n-mers may consist of either the same or different entities. 

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