Complexes of iron(III) salen and saloph Schiff bases with bridging 2,4,6-tris(2,5-dicarboxyphenylimino-4-formylphenoxy)-1,3,5-triazine and 2,4,6-tris(4-carboxyphenylimino-4′-formylphenoxy)-1,3,5-triazine

Abstract

Complexes of iron(III) salen and saloph Schiff bases with bridging 2,4,6-tris(2,5-dicarboxyphenylimino-4-formylphenoxy)-1,3,5-triazine and 2,4,6-tris(4-carboxyphenylimino-4¢-formylphenoxy)-1,3,5-triazine Abstract Four new trinuclear Fe(III) complexes involving tetradenta Schiff bases N,N 1 -bis(salicylidene) ethylenediamine-(salenH 2 ) or bis(salicylidene)-o-phenylenediamine-(salophH 2 ) with 2,4,6-tris(2,5-dicarboxyphenylimino-4-formylphenoxy)-1,3,5-triazine (DCPI-TRIPOD) or 2,4,6-tris(4-carboxyphenylimino-4¢-formylphenoxy)-1,3,5-triazine (CPI-TRIPOD) have been synthesized and characterized by means of elemental analysis carrying out 1 H-n.m.r., i.r. spectroscopy, thermal analyses and magnetic susceptibility measurements. The complexes can also be characterized as high-spin distorted octahedral Fe III bridged by carboxylic acids. The tricarboxylic acids play a role as bridges for weak antiferromagnetic intramolecular exchange.

Synthesis and characterization of dendrimeric melamine cored [salen/salophFe(III)] and [salen/salophCr(III)] capped complexes and their magnetic behaviors

“…Obtained tripodal oxySchiff bases were characterized by their elemental analyses, thermal analyses, 1 H NMR, and FT-IR, AAS and mass spectral data. [34][35][36][37][38][39]. These complexes are the examples of tripodal multinuclear complexes bridged by carboxylate anions to the iron and chromium centers (Scheme 2).…”

“…The vibrations of the azomethine C N, triazine C N and C-O-C of the free ligands were observed at 1618-1605, 1574-1560 and 1375-1359 cm −1 range, respectively [34][35][36][37][38]42,43]. In the complexes, the fact that these bands were shifted to lower frequencies has indicated that oxygen atoms of the dendrimeric oxy-Schiff base ligands are coordinated with the ligand complexes.…”

“…In the complexes, the fact that these bands were shifted to lower frequencies has indicated that oxygen atoms of the dendrimeric oxy-Schiff base ligands are coordinated with the ligand complexes. In the ligands 2,4,6-tris(4-(4,6-bis(4-carboxyphenyloxy)-1,3,5-triazine-2-yloxy)benzimino)-1,3,5-triazine 4 or 2,4,6-tris(4-(4,6-bis(3,5-dicarboxyphenyloxy)-1,3,5-triazine-2-yloxy)benzimino)-1,3,5-triazine 5 the band at 3263-3244 cm −1 can be assigned to the carboxylate OH group vibrations [10,[34][35][36][37][38]. Bands at 1699-1697 cm −1 for all complexes were assigned to C O groups due to the coordination of [Fe(salen)], [Fe(saloph)], [Cr(salen)] and [Cr(saloph)] with COO groups.…”

“…In the dendrimeric-multinuclear complexes, that these bands at 3263-3244 cm −1 for carboxylate OH group vibrations disappeared can also be attributed to the coordination of COO groups with the metal. The bands in the 534-542 and 466-476 cm −1 ranges can be attributed to the M-N and M-O stretching modes [34][35][36][37][38]44]. …”

“…We are also interested in dendrimeric multinuclear systems formed by the carboxylato bridges because of some satisfactory work concerning this bridge and associated data have appeared in the literature [34][35][36][37][38].…”