Complexes of iron(III) and chromium(III) salen and salophen Schiff bases with bridging 1,3,5-triazine derived multidirectional ligands

A new synthetic route for preparing multidirectional ligands was developed by using 2,4,6‐trichloro‐1,3,5‐triazine (cyanuric chloride) as core. The reaction included the selective substitutions of 4‐aminobenzoic acid onto three chlorides of the triazine ring via a stepwise manner at 1:1, 1:2, or 1:3 equiv. and 0, 25, 130°C, respectively. An efficient synthesis of a novel class of “multidirectional ligands” has been developed based on high‐yielding chloride substitutions of 2,4,6‐trichloro‐1,3,5‐triazine by amines. Sixteen new mono‐, di‐, tri‐, and tetra‐nuclear Fe(III) and Cr(III) complexes involving tetradenta Schiff bases N,N′‐bis(salicylidene)ethylenediamine‐(salenH2) or bis(salicylidene)‐o‐phenylenediamine‐(salophenH2) with two new 1,3,5‐triazine derived multidirectional ligands were synthesized and characterized by means of elemental analysis, 1H NMR, FT‐IR spectroscopy, LC‐MS analysis, AAS, thermal analysis, and magnetic susceptibility measurements. The complexes were also characterized as low‐spin distorted octahedral Fe(III) and Cr(III) bridged by carboxylic acids. It was understood that the [{Fe(salen)/(salophen)}2O] and [{Cr(salen)/(salophen)}2O] containing compounds could be represented by the electronic structure of t 2g5e g0 and t 2g3e g0. J. Heterocyclic Chem., (2011).