INFLUENCE OF THE POSITION OF THE METHYL-GROUPS ON DONOR-ACCEPTOR PROPERTIES OF SELECTED METHYLPYRAZOLES TOWARDS COBALT(II), NICKEL(II), COPPER(II), ZINC(II) AND CADMIUM(II) IN AQUEOUS-SOLUTION

The formation of coordination compounds has been studied of 1,3,5-trim ethylpyrazole (1,3,5-TMePz), 3,4,5-trimethylpyrazole (3,4,5-TMePz), 1, 3,4-trimethylpyrazole (1,3,4-TMePz), 1,4,5-trimethylpyrazole (1,4,5-TM ePz) and 1,3,4,5-tetramethylpyrazole (1,3,4,5-TeMePz) with Co(II), Ni( II), Cu(II), Zn(II) and Cd(II) in aqueous solution. Stability constant s, beta(n), of the complexes have been determined. The influence of th e position of the methyl groups on the donor-acceptor properties of py razole and its derivatives has been discussed.