Journal of Hazardous Materials 175 (2010) 532–539 Contents lists available at ScienceDirect Journal of Hazardous Materials journal homepage: www.elsevier.com/locate/jhazmat Synthesis and characterization of dendrimeric melamine cored [salen/salophFe(III)] and [salen/salophCr(III)] capped complexes and their magnetic behaviors S¸ aban Uysal ∗ , Ziya Erdem Koc¸ Department of Chemistry, Faculty of Science, Selcuk University, Campus of Alaaddin Keykubat, 42075 Selcuklu, Konya, Turkey article info Article history: Received 10 August 2009 Received in revised form 2 October 2009 Accepted 13 October 2009 Available online 20 October 2009 Keywords: s-Triazine Melamine Cyanuric chloride Salen Saloph Schiff bases abstract 2,4,6-Tris(4-hydroxybenzimino)-1,3,5-triazine [1] 2 has been synthesized from the reaction of 1 equiv. melamine (2,4,6-triamino-1,3,5-triazine) and 3 equiv. 4-hydroxybenzaldehyde. Then, 2,4,6-tris(4-(4,6- dichloro-1,3,5-triazine-2-yloxy)benzimino)-1,3,5-triazine 3 has been synthesized from the reaction of 1 equiv. 2 and 3 equiv. cyanuric chloride. And then, two new triazine centered dendrimeric ligands 2,4,6-tris(4-(4,6-bis(4-carboxyphenyloxy)-1,3,5-triazine-2-yloxy)benzimino)-1,3,5-triazine 4 and 2,4,6- tris(4-(4,6-bis(3,5-dicarboxyphenyloxy)-1,3,5-triazine-2-yloxy)benzimino)-1,3,5-triazine 5 have been synthesized from the reaction of 1 equiv. 3 and 6 equiv 4-hydroxybenzoic acid or 5-hydroxyisophtalic acid. Finally, eight new multinuclear Fe(III) and Cr(III) complexes involving tetradenta Schiff bases N,N ′ -bis(salicylidene)ethylenediamine-(salenH 2 ) or bis(salicylidene)-o-phenylene diamine-(salophH 2 ) with 4 or 5 have been synthesized and characterized by means of elemental analysis, 1 H NMR, FT-IR spectroscopy, thermal analyses and magnetic susceptibility measurements. The complexes can also be characterized as low-spin distorted octahedral Fe(III) and Cr(III) bridged by carboxylic acids. © 2009 Elsevier B.V. All rights reserved. 1. Introduction An important class of compounds having anticancer, antitumor, antiviral and antifungal activity consists of substituted s-triazine derivatives. These compounds have been used in the treatment of depression and hence gained considerable significance. These are valuable bases for estrogen receptor modulators [2] and also used as bridging agents to synthesize herbicides and in the production of drugs or polymers [3]. Melamine resins have been used in many applications includ- ing the manufacture of plastic dishes under the trade name Melmac. 1,3,5-Triazine derivatives are widely used as herbicides [4], drugs [5] or polymers [6], like melamineformaldehyde that has excel- lent thermal and electrical properties [7]. Phenolic melamine has a good non-flammability owing to containing nitrogen in its chemical structure [8]. We have reported here that dendrimeric Schiff bases including hexacarboxylic and dodecacarboxylic groups have been synthe- sized to be a new template. The reaction of melamine (C 3 N 6 H 6 ) with 3 equiv. of 4-hydroxybenzaldehyde in benzene has given the desired triazomethine groups and triphenolic groups in a single step. Phenolic–OH groups [9,10] were then reacted to trimeric ∗ Corresponding author. Tel.: +90 532 303 30 35. E-mail addresses: uysal77@hotmail.com, suysal@selcuk.edi.tr (S¸ . Uysal). cyanuric chloride (C 3 N 3 Cl 3 ) as single directional at 0–5 ◦ C. Then, the obtained product was reacted under reflux with 6 equiv. 4-hydroxybenzoic acid and 6 equiv. 5-hydroxyisophthalic acid [11–15]. It may be useful to stress at the point that the new prod- ucts mentioned above are the main output of this work. These are the first in the literature and we call them “oxy-Schiff Bases” due to literature [9,10]. The magnetochemical properties of the -oxo-bridged com- plexes [{Fe(salen)} 2 O] [(salenH 2 = N,N ′ -bis(salicylidene)ethylene diamine)] and [{Fe(saloph)} 2 O] [(salophH 2 = bis(salicylidene)-2- phenylenediamine)] and their X-ray studies have widely been presented in the literature [16–19]. The reaction of [{Fe(salen)} 2 O] with carboxylic acids have been given by Wollmann and Hendrick- son [20]. Chromium is a unique transition metal ion, which has been established to be biologically significant at all the levels of liv- ing organisms [21]. Out of the two stable oxidation states of chromium, -VI and -III, trivalent chromium has been shown to play a positive role in controlling carbohydrate and lipid metabolism [22]. A Schiff base complex of chromium(III), [Cr(salen)(OH 2 ) 2 ] + , was found to enhance insulin activity, and insulin derived with the same was found to exhibit higher activity in glucose metabolism in animal models when compared with either free insulin or other derivatives [23,24]. Their asymmetric catalytic reactions have been described including oxidations, additions and reductions such as epoxidation of olefins, epoxide ring 0304-3894/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.jhazmat.2009.10.038