Potentiometric and Biocidal Studies of Ternary Complexes of Some Transition Metals with 2-Carboxy,2' - -Hydroxy Diphenylamine (DPHC) and Some Bidentate Ligands

Chemical Laboratories, Agra College, Agra-282-002

Manuscript received 12 December 1983, accepted 25 March 1984

Synthesis and characterisation of a new ligand, 2-carboxy,2'-hydroxy diphenylamine has been described. The potentiometric studies on the binary and ternary complexes of the above ligand with some transition metal ions (Cu²⁺, Ni²⁺, Zn²⁺ and Cd²⁺) have been carried out. The dissociation constants of free ligand and the stability constants for 1 : 1, M-L and 1 : 1 : 1, M-L-L^' [M- metal ions, L- 2-carboxy ,2' -hydroxy diphenylamine (DPHC) and L'- nitrilotriacetic acid (NTA)] have been evaluated at 25 ± 1^o in 2.5% ethanolic medium. The systems 1 : 1 : 1, M(II)-DPHC-HQ (HQ- 8-hydroxyquinoline) were also studied pH-metrically. The copper complex was isolated, characterised and tested for its fungicidal and bactericidal activities towards some selected species.