The use of hydrogenated Schiff base ligands in the synthesis of multi-metallic compounds

Abstract

The synthetic utility of tris-((2-hydroxybenzyl)-aminoethyl)amine (H6TrenSal) and tris-((2-hydroxy-5-bromobenzyl)-aminoethyl)amine (H6Tren5BrSal) are investigated. A range of monomeric complexes with general formula [(H6TrenSal) M][NO3] with nickel, copper and zinc are reported and crystallographically analysed. Nickel adopts three motifs which are different to that observed for copper and zinc. The use of these species as platforms for the synthesis of more complex systems in conjunction with the lanthanoids are explored. Copper and zinc do not follow a similar reaction pathway to nickel. While nickel forms the expected trimetallic motif [{(TrenSal)Ni}(2)Ln(HOMe)](+), copper forms a copper trimetallic motif. In contrast to both nickel and copper, reactions with [(H6TrenSal)Zn](+) produce lanthanoid based products namely [(H6Tren5BrSal)Gd(NO3)(3)] and [{(H6TrenSal)Ce}(2)-mu(2)-O-2]

Synthesis, characterization and anti-microbial studies of mixed D/F trinuclear complexes using N₄O₃ potentially heptadentate Schiff-Base ligand

“…Yield 77.7% (Mustapha et al, 2008;Kanesato et al, 2000;Richarson et al, 1968) (Kahn et al, 1999). Yield 62% (Mustapha et al, 2011;Mustapha et al, 2008;Simon et al, 2003;Mustapha et al, 2009 andKahn et al, 1999) (Mustapha et al, 2011;Mustapha et al, 2008;Simon et al, 2003;Mustapha et al, 2009 andKahn et al, 1999) Insoluble Insoluble Insoluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Insoluble Insoluble Insoluble The Electronic spectra The spectrum of the free ligand shows a band at λ max 380nm and 420nm which is attributed to (π π*) and (n π) transition.…”

“…Among the large number of ligand frameworks studied, Schiff base derivatives of the TREN moiety [N(CH 2 CH 2 NH 2 ) 3 ] were found to be very effective in the design of multinuclear compounds, most especially those derived from the reaction of salicylaldehyde with TREN (Mustapha et al, 2011;Mustapha Simon et al, 2003 andMustapha et 2009). This plunged chemists to the search of such compounds and concentrate on studying their chemistry including their coordination mode , we have reported a catalog of such compounds recently (Mustapha et al, 2009 andMustapha 2011), while in previous study a family of Tren5BrSal ligand have been reported to have an application as chelator of Tc-99 in nuclear medicine (Essig et al, 2001). metal compounds are receiving increasing attention.…”

Metal complexes as potential ligands: The deprotonation of aminephenolate metal complexes

“…Our previous work on tris-(2-hydroxybenzyl)-aminoethylamine (H6TrenSal 1 ; Fig. 1a) identified an interesting pair of encapsulated cationic nickel complexes namely [(H6TrenSal)(H 2 O)Ni] + and [(H6TrenSal)Ni] + [3]. Both of these species are six coordinate.…”

“…It is intriguing that the nickel complexes do not naturally deprotonate to form neutral species as is found for the related tris-(2-hydroxy-5-bromo-benzyl)-aminoethylamine (H6Tren5BrSal; Fig. 1d) [3]. Our interest in this process stems not just from our desire to design and synthesise further multimetallic complexes but to try an understand why [(H6Tren-Sal)Cu] + and [(H6TrenSal)Zn] + (Fig.…”

“…Our interest in this process stems not just from our desire to design and synthesise further multimetallic complexes but to try an understand why [(H6Tren-Sal)Cu] + and [(H6TrenSal)Zn] + (Fig. 1c) do not readily form trimetallic lanthanoid complexes similar to the corresponding nickel complex [3][4][5][6]. It is likely that the altered reaction pathway stems either from the nature of the uncoordinated phenolates or the manner in which the ligands deprotonate during reaction.…”