Thermodynamics of the Interaction of Bivalent Transition Metal Ions with Phthalanilic Acids

Department of Chemistry, University of Roorkee, Roorkee-247 667

Manuscript received 30 January 1984, accepted 10 August 1984

The thermodynamic stepwise stability constants, free energy, enthalpy and entropy changes for the formation of Mn^II, Fe^II, Co^II, Ni^II and Cu^II ions with phthalanilic, 4-methylphthalanilic, 4-methoxyphthalanilic, 4-chlorophthalanilic, 4-bromophthalanilic and 4-nitrophthalanilic acids were determined. Analysis of the data indicated the chelation of phthalanilic acids through nitrogen of secondary amide and carboxylate groups.