A Novel Transamination Induced by Terpyridine Ligand Coordinated on Cobalt(III) Ion

Abstract

The reaction of salicylidene-l-alanine with the Co(III) complex involving 2,2′:6′,2″-terpyridine (terpy) in aqueous ethanol solution afforded a peculiar transamination to form the complex, [Co(α-hydroxy salicylidene-o-hydroxybenzylamine)(terpy)]+, whose structure has been confirmed by X-ray structure analysis and positive FAB mass spectrometry.

Reactions at the azomethine CN bonds in the nickel(ii) and copper(ii) complexes of pyridine-containing Schiff-base macrocyclic ligands

“…Several examples of double-bond migration in Schiffbase metal complexes have been reported in the literature. [58][59][60][61][62][63] These isomerization reactions are similar to transaminations catalyzed by vitamin B6 or other pyridoxal derivatives. 60, 64 The mechanisms of pyridoxal-dependent transaminations involve deprotonation of the C-H bond that yields a resonancestabilized anion, followed by an addition of a proton to another carbon atom (Scheme 4, pathway A).…”

An infinite two-dimensional hybrid water–chloride network in a 4′-(furan-2-yl)-2,2′:6′,2′′-terpyridine nickel(II) matrix

“…Hybrid water-chloride associates incorporated in various crystal matrixes are one of the most interesting combinations in water clusters research due to their fundamental importance for understanding water-halide interactions in the atmosphere, the ocean and in biological systems (Inumaru et al, 2008;Kumar et al, 2011;Lakshminarayanan et al, 2006;Li et al, 2008). According to a search of the Cambridge Structural Database (CSD Version 5.37, May 2016; Groom et al, ISSN 2056-9890 2016), there are about nine examples with water-chloride hydrogen bonds forming one-dimensional tapes (Boyer et al, 2011;van Holst et al, 2008;Kepert et al, 1999;Jitsukawa et al, 1994), two-dimensional (Kepert et al, 1994;Chowdhury et al, 2011;Duan et al, 2016) and three-dimensional (Figgis et al, 1983;Pruchnik et al, 1996) networks from 2,2 0 :6 0 ,2 00 -terpyridine ligands. When 4 0 -substituted terpyridines with phenyl, pyridyl, imidazolyl rings were considered, two-dimensional and three-dimensional water-chloride networks with two chloride ions and at least six water molecules were found (Constable et al, 1990;Kou et al, 2008;Chen et al, 2013;Fernandes et al, 2008;McMurtrie & Dance, 2010;Padhi et al, 2010;Indumathy et al, 2008;Mahendiran et al, 2016).…”

Synthesis, crystal structure, spectroscopy, and magnetism of a mixed valence Co(III)–Co(II)–Co(III) complex stabilized by N-(2-hydroxybenzyl)salicylaldimine

“…Co(III)-Co(II)-Co(III) complex 507 H 2 L a and its substituted derivatives can stabilize some transition metal ions of higher oxidation states, such as Co III [27] and Mn IV [28,29]. At the same time coordination of Co III with L 2À a may play an important role for C-N single bond cleavage of L 2À a and in situ ligand transformation.…”