Stereochemical factors affecting intramolecular inter ligand interaction in mixed ligand complexes

Abstract

The binary and ternary complexes of the types [MA], [MA₂] and [MAL] have been studied, where M = Cu(II), Ni(II) and A = mannich bases synthesized by the condensation of different amino acids with salicylaldehyde, followed by reduction, such as, 2-(<em>o</em>-hydroxybenzylamino] acetic acid (HBAA) (A¹), 2-(<em>o</em>-hydroxybenzylamino)propionic acid (HBAP) (A²)<em>, </em>2-(<em>o</em>-hydroxybenzylamino)- 3-(phenyl)propionic acid (HBAPP) (A³), 2-(<em>o</em>-hydroxybenzylamino)-3-(<em>o</em>-hydroxyphenyl)propionic acid (HBAHPP) (A⁴)<em>, </em>2-(<em>o</em>-hydroxybenzylamino)-3-(<em>p</em>-indolyl)propionic acid (HBAIP) (A⁵) and L= glycine (L¹)<em>, </em> ɑ-alanine (L²)<em>, </em>phenylalanine (L³),tyrosine (L⁴) or tryptophan (L⁵). The stability constants of these complexes have been determined potentiometrically using SCOGS computer programme. The probable reasons for more or less negative <img src='/image/spc_char/delta.gif' border=0>log <em>K </em>values of the ternary complexes have been discussed.