Interphase processes involving hydrazine derivatives. IX - The influence of anion pair upon the extraction of some cations and of arginine by means of crown ethers

Utilization of liquid-liquid interphase processes mediated by crown ethers facilitated the establishment of the influences which determine the stabili ty of supramolecular complexes of(CE...M)(+)A(-) type (where CE = crown eth er 12-C-4, 15-C-5, 18-C-6, B15-C-5 and DB18-C-6; M+ = cation, Li+, Na+, Kand arginineH(+) A(-) = anion originated in HA acids 2,2-diphenyl-1-picryl- hydrazine (DPPH2), 2-(p-nitrophenyl)-2-phenyl-1-picrylhydrazine (NO2DPPH2) and 2,2-(p-nitrophenyl)-1-picrylhydrazine ((NO2)PPPH2)). Therefore the K-ex values were determined in the case in which DPPH2 was utilized; the values obtained were compared to those determined in the case in which NO2DPPH2 a nd (NO2)(2)DPPH2 were utilized. The diameters of CE cavities and M+ as well as the pK(a) values of HA acids were correlated with Ig K-ex values by mea ns of multilinear regression type equations.