Thermodynamic aspects of the polyazacycloalkane complexes with cations and anions

Synthesis, Crystal Structures and Lithium Encapsulation by Some Phenolic Aza Cages

“…In the in the basic strength as the degree of protonation increases. This behaviour is expected for all aza cages, [11] in which case of 2, precipitation of the lithium complex prevents any equilibrium constant determination. The equilibrium conpositive charges are forced close to each other as a result of the molecular topology, thus making further addition of stants reported in Table 1 2ϩ species is prevalent in solution, showed twelve peaks, due to a reduced C s symmetry in solution on the protonation constant involved is too high to be measurable in the absence of Li ϩ , as stated in the previous section, the NMR time scale, instead of the expected C 2v .…”

On the Signalling Pathways and CuII‐Mediated Anion Indication of N‐meso‐Substituted Heptamethine Cyanine Dyes

“…1.5-3.1) because of the energy necessary to transform all the nitrogen atoms from the endo to exo conformation. [58] However, in the case of 1, due to the bulkiness of the attached chromophore one of the nitrogen atoms is already in the exo conformation at neutral pH, most probably facilitating the other conformational changes. The second protonation step at pK a = 1.6 is then irreversible.…”

Synthesis, protonation constants of a series of triazamacrocycle methylenephosphonic acids

“…On the other hand, the surprising complexation properties of azacrowns and their derivatives were widely studied [7][8][9]. It was found that the selectivity of some macro azacycles is so high that there is somewhat 20 orders of magnitude difference in the stability constants of the complexes between the azacrowns and some ions [10].…”