Mixed ligand complexes of Al [III], In [III] and Ti [I] with 6, 7 dihydroxy-4-methylcoumarin as primary ligand and some amino acids as secondary ligand

ABSTRACT

Formation constants [log KMA MAL] of the mixed ligand complexes of the type MAL [where M = Al[3], In[3] and Tl[1], A = 6,7-dihydroxy-4-methylcoumarin and L = threonine, phenylalanine, glutamic acid, aspartic acid, glycine and alanine] were determined pH metrically in ethanol-water mixture [30% v/v] at 25C and mu = 0.1 [mol dm-3 NaClO4] by using the extension of Irving-Rossotti technique to ternary systems. The formation of 1 1 1 [M A L] species was evidenced. The stability sequence with respect to metal ions were found to be Al[3] > In[3] > Tl[1]