Ternary complexes of nickel(II) involving ampicillin and some potentially bi- and tridentate ligands

Department of Chemistry, Manonmaniam Sundaranar University, Abishekapatti, Tirunelveli-627 012, India

Department of Chemistry, National Engineering College, K. R. Nagar, Kovilpatti-628 503. India

Manuscript received 1 September 1999. revised 4 January 2000, accepted 1 April 2000

The multiple equilibrium studies involved in the Ni^II-ampicillin (amp)(A)-1,2-diaminopropane, 1,3-diaminopropane, DL,-2,3- diaminopropionic acid, DL-2,4-diaminobutyric acid and DL-2,5-diaminovaleric acid(B) systems show the presence of NiABH₂, NiABH. NiAB and NiABH_-1 ternary species. In the NiABH₂ species one proton is attached with ligand (A) and the other with ligand (B), while in the NiABH species the site of protonation is ligand (B). In the NiABH_-1 species the deprotonation occurs with ligand (A). In all these systems, in the NiAB species the binding of the ligands A and B is similar to their binding in their respectile binary systems.