Probing the Dinucleating Behaviour of a Bis‐Bidentate Ligand: Synthesis and Characterisation of Some Di‐ and Mononuclear Cobalt(II), Nickel(II), Copper(II) and Zinc(II) Complexes of 3,5‐Di(2‐pyridyl)‐4‐(1H‐pyrrol‐1‐yl)‐4H‐1,2,4‐triazole

Abstract

As a probe of the dinucleating ability of the known but little studied bis-bidentate ligand 3,5-di(2-pyridyl)-4-(1H-pyrrol-

Synthesis, crystal structure and magnetic property of the novel dinuclear nickel(II) complex with 4-(p-methoxyphenyl)-3,5-bis(pyridine-2-yl)-1,2,4-triazole

“…The best least squares fit parameters gave g = 2.16, J = ) 8.43(6) cm )1 , zJ 0 ¼ 0:8ð1Þ cm À1 . The coupling constant is similar to the corresponding value observed for [Ni 2 (pldpt) 2 ])(ClO 4 ) 4 and [Ni 2 (pldpt) 2 (H 2 O) 4 ](BF 4 ) 4 [13] and less than that observed in related nickel(II) complexes of other 4-substituted 3,5-bis(pyridine-2-yl)-1,2,4-triazole [1, 6] ( Table 3).…”

“…Compared with alkyl-substituted 1,2,4-triazole [9,10], dinuclear complexes containing triaryltriazole ligand have been rarely studied so far [11][12][13]. Recently we have synthesized some triaryltriazole compounds [14][15][16], which could be acted as doubly-bidentate chelating ligands because of their structural similarity to 4-amino-3,5-bis(pyridine-2-yl)-1,2,4-triazole (NH 2 BPT) [1].…”

Structural characterisation of mononuclear zinc(ii) complexes of 4-methyl-3,5-di(2-pyridyl)-4H-1,2,4-triazole with three-atom co-ligands: [ZnII(medpt)2X]ClO4 (X = NCS−, N3 −, NO2 −)

“…Given that all copper(II) complexes of 4-substituted 3,5-di(2-pyridyl)-4H-1,2,4-triazoles described so far are six-coordinate, apart from the two exceptions mentioned earlier, and that only six-coordinate zinc(II) complexes of 4-substituted 3,5-di(2-pyridyl)-4H-1,2,4-triazoles have been reported to date [10][11][12][13], it was decided to examine the reaction of medpt with Zn(ClO 4 ) 2 Á6H 2 O in combination with the triatomic co-ligands NCS -, N 3 -and NO 2 -in an attempt to obtain complexes featuring new coordination geometries. In this paper, we report the synthesis and the structural characterisation of the first two 2:1 type five-coordinate zinc(II) complexes of any 4-substituted 3,5-di(2-pyridyl)-4H-1,2,4-triazole and of a 2:1 type six-coordinate zinc(II) complex displaying a highly irregular coordination environment.…”

Syntheses and crystal structures of two novel Cu(II) and Co(II) complexes with 3-methyl-4-(p-bromophenyl)-5-(2-pyridyl)-1,2,4-triazole

“…Over the past few decades, 1,2,4-triazole derivatives have attracted much attention, mainly because of the fact that these molecules can act as flexible bridging ligands and spacers between transition metal ions [1][2][3]. Some complexes containing substituted 1,2,4-triazole ligands show interesting magnetic properties [4][5][6][7], especially, some iron(II)-triazole complexes have spin-crossover properties which can be used in molecular electronics [8], as information storage [9] and switching materials [10].…”