HEXADENTATE N4O2 AMINE PHENOL COMPLEXES OF GALLIUM AND INDIUM

{Several linear N4O2 amine phenols based on triethylenetetramine (trien) were prepared and characterized by spectroscopic techniques (H(2)bad = 1,10-bis(2-hydroxybenzyl)-1,4,7,10-tetraazadecane; H(2)Clbad = 1,10-bis(2-hydroxy-5-chlorobenzyl)-1,4,7,10-tetraazadecane; H(2)Brbad = 1,10-bis(2-hydroxy-5-bromobenzyl)-1,4,7,10-tetraazadecane). These amine phenols were prepared by the in situ reduction of the corresponding Schiff bases, which were in turn derived from condensation reactions of trien with the appropriately substituted salicylaldehyde. Characterization of the amine phenols revealed two hydroxybenzyl groups connected to the trien backbone via the terminal primary amine nitrogen atoms. There are six potential sites for coordination to a metal ion: four amine nitrogens and two phenolate oxygens. Acetone adducts, prepared by refluxing the amine phenols in acetone, contained two imidazolidine rings, each of which was formed by the reaction of acetone with one inner and one terminal amine nitrogen. Monocationic metal complexes were obtained from the reactions of Ga3+ and In3+ with the N4O2 amine phenols in the presence of 2 equiv of base (acetate). The molecular structure of [Ga(Brbad)]-ClO4.(CH3)(2)SO (C22H32Br2ClGaN4O7S