Synthesis and Characterization of Novel Substituted 3,6‐Di(2‐pyridyl)pyridazine Metal‐Coordinating Ligands

Abstract

The synthesis of novel functionalized 3,6-di(2-pyridyl)pyridazines via an inverse electron demand Diels−Alder reaction between the corresponding 3,6-di(2-pyridyl)-1,2,4,5-tetrazine and various alkynes is reported. The resulting 3,6-di(2-pyridyl)pyridazines were investigated using X-ray crystallography, IR spectroscopy, and NMR spectroscopy, whereby several 2D NMR spectroscopic techniques were exploited to

Crystal structure of 3,6-di-2-pyridinyl-4-pyridazine carbonitrile, C15H9N5

“…The synthesis of 3,6-di(2-pyridyl)tetrazine and its utilization in inverse-type DielsAlder reactions was rst described by Butte and Case [5]. In continuation of that work other groups have reported similar cycloadditions to the 3,6-di(2-pyridyl)tetrazine, resulting in monosubstituted octyl, carboxy ethyl or tetrahydropyranyl diethyl ethers of methanol, hexanol and fullerenes [4,15,16].…”

“…These compounds can act as metal coordinating ligands for copper, silver and nickel ions resulting in grid-like metal complexes [11,12]. In addition, many binuclear metal complexes of these ligands with nickel, copper and platinum have been reported [4,13]. Highly functionalized pyridazine are easily accessible via an inverse Diels-Alder reaction between the 1, 2, 4, 5-tetrazine and a wide variety of acetylenes, whereby the tetrazine acts as the electron de cient diene [4,14].…”

“…In addition, many binuclear metal complexes of these ligands with nickel, copper and platinum have been reported [4,13]. Highly functionalized pyridazine are easily accessible via an inverse Diels-Alder reaction between the 1, 2, 4, 5-tetrazine and a wide variety of acetylenes, whereby the tetrazine acts as the electron de cient diene [4,14]. The synthesis of 3,6-di(2-pyridyl)tetrazine and its utilization in inverse-type DielsAlder reactions was rst described by Butte and Case [5].…”

“…The ligand was prepared using the method of Butte and Case [4,5]. 3,6-di(2-pyridyl)tetrazine (1.0 g, 6.8 mmoles) and (1.1 g, 20.73 mmoles) of acrylonitrile were dissolved in 25 mL of toluene.…”

Microwave-Assisted Synthesis of Bioactive Six-Membered Heterocycles and Their Fused Analogues

“…The pyridazine structure is found within a number of herbicides and several pharmaceutical drugs ( Figure 9) [131][132][133][134][135][136]. Substituted pyridazines have attracted much attention in the fields of organic chemistry for mechanistic investigations [137][138][139][140][141][142][143], as well as in the field of natural products synthesis [140,[143][144][145][146]. …”