COMPLEX-FORMATION OF SOME ANILINIUM ION DERIVATIVES WITH 18-CROWN-6, 1,10-DIAZA-18-CROWN-6 AND CRYPTAND C222 IN ACETONITRILE, DIMETHYLFORMAMIDE AND THEIR 1 1 MIXTURE/

The complexation reactions between the protonated salts of aniline, o- hydroxy aniline, o-amino aniline and 2,3-benzo aniline (alpha-naphthyl amine) and macrocyclic ligands 18-crown-6,1,10-diaza-18-crown-6 and cr yptand C222 have been studied conductometrically in acetonitrile, dime thylformamide and their 1:1 (mol-mol) mixture at 25 degrees C. Formati on constants of the resulting 1:1 complexes were determined from the c omputer fitting of the molar conductance-mole ratio data. In all cases studied, the stability of the complexes decreases in the order C222 > 1,10-diaza-18-crown-6 > 18-crown-6. There is also an inverse relation ship between the stabilities of the complexes and the Gutmann donor nu mber of the solvents. It was found that, in the aromatic anilinium ser ies used, increasing the bulkiness of the organic substituent in the o rtho position results in a loss of complex stability.