Determination of stability constant of some transition metal ions chelates with substituted pyrazoles
نویسنده
چکیده
The stability constants of the complexes of Cu (II), Co (II) and Ni (II) ions with 3-(3’-nitrophenyl)4-(4"-chlorobenzoyl)-5-(2-hydroxyphenyl) pyrazole (L1), 3-(4’-chlorophenyl)-4-(4"-chlorobenzoyl)-5-(2hydroxyphenyl) pyrazole (L2), 3-(4’-methoxyphenyl)-4-benzoyl-5-(2-hydroxyphenyl) pyrazole (L3), 3(4-bromophenyl)-4-furoyl-5-(2-hydroxyphenyl) pyrazole (L4) have been determined by the pH-metric method at 0.1M ionic strength at 28 ± 0.10C in 70% dioxane-water mixture. The data obtained were used to estimate the values of proton-ligand (pK) and metal-ligand (logK) stability constants. It is observed that Cu (II), Co (II) and Ni (II) metal ions form 1:1 and 1:2 complexes with all the ligands.
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تاریخ انتشار 2010