Bidentate Chelate Compounds. III. Metal Complexes of Some Pyridyl-Imidazole Derivatives

Abstract

The bases 2-(2'-pyridyl)imidazole and 2-(6'-methyl-2'-pyridyl)imidazole have been synthesized and shown to be capable of functioning as bidentate chelating agents. The cations of certain of the complex salts they and 2-(2 '-pyridyl)benzimidazole form with transition metal salts can be deprotonated with bases to "neutral" complexes. However, it has not proved possible by treatment with alkalies to deprotonate such salts so as to obtain complexed metal in the anions.

Crystal structure of 2-(2′-pyridyl)imidazole, C8H7N3

“…The title molecule 2-(2'-pyridyl)imidazole (py-imH) has been widely used as ligand in coordination chemistry [1][2][3][4] [14,15]. It is also known to yield to iron(II) complexes exhibiting spin crossover behaviour in solution [16,17] as well as in the solid state [18][19][20][21][22].…”

Investigation on the complex of diperoxovanadate with 2-(2′-pyridyl)-imidazole

“…2-(2 0 -Py)-Imi shown in Fig. 1 was synthesized according to the literature [38]. To form the ternary system of NH 4 VO 3 /H 2 O 2 / L (where L = Py, Imi, and 2-(2 0 -Py)-Imi), NH 4 The diperoxovanadate complex was prepared by adding 10 mL H 2 O 2 (30%, w/v, solution) and 1.16 g NH 4 VO 3 (10 mmol) to 50 mL distilled water.…”

Hydrothermal synthesis of a 2-(2-pyridyl)imidazole derivative and its copper(II) and zinc(II) complexes

“…With quinoline-8-thiol, it is comparatively easy to form a cyclic quarternary compound by direct alkylation with dibromoethane [7]. However, for 2-(2-pyridyl)imidazole it was reported that the reaction with dibromoethane gives dimeric 1,2-bis-[2-(2-pyridyl)imidazolyl]ethane (Scheme 1), instead of a cyclic quarternary salt; this was presumed to be due to the distance between the pyridine nitrogen and the saturated amine nitrogen [8]. In this article, we describe a hydrothermal method to cyclize 2-(2-pyridyl)-imidazole with dibromoethane, 6,7-dihydro-pyrido[2 0 ,1 0 :3,4]pyrazino[1,2-a]imidazol-5-ium-bromide (LBr Á H 2 O) (Scheme 1).…”