Kinetics and mechanism of substitution of bis(tptz)iron(II) by 2,2′-bipyridine and 1,10-phenanthroline

摘要: The kinetics of substitution Fe(tptz)2+2 by 2,2′-bipyridine and 1,10-phenanthroline have been investigated in acetate buffers the 3.6–5.6 pH range employing stopped-flow spectrophotometry. These reactions are very fast complete within 5 s. rate is linearly dependent on [phen] [bpy]2, increases with increase pH. Suitable mechanisms proposed involving unprotonated form entering ligand, viz. bipyridine/phenanthroline as reactive species. pKa values bipyridine phenanthroline, determined from kinetic data, agreement literature values. It concluded that substitutions iron(II)-diimine complexes also occur an associative mechanism.