N′-[1-(Pyrazin-2-yl)ethylidene]pyrazine-2-carbohydrazide

Abstract

The title compoud, C 11 H 10 N 6 O, was synthesized by the condensation reaction of pyrazine-2-carbohydrazide with 2-acetylpyrazine in ethanol. The dihedral angle between the pyrazine rings is 4.7 (3) . In the crystal, aromatic -stacking [centroid-centroid separations = 3.606 (5) and 3.671 (5) Å ] connect the molecules into stacks propagating in the [010] direction. A weak C-HÁ Á ÁN interaction is also observed. The crystal studied was refined as a two-component twin. Structure descriptionThe Schiff base acylhydrazone ligand has been well studied and used in supramolecular chemistry (Stadler & Harrowfield, 2009) The dihedral angle between the pyrazine rings is 4.7 (3) (Fig. 1). The C2-N2 bond length is 1.291 (7) Å , which is shorter than C1-N1 [1.362 (7) Å ], showing that C2-N2 has strong double-bond character. The N-H grouping is sterically hindered from forming hydrogen bonds but a short intramolecular N-HÁ Á ÁN contact occurs (Table 1). In the crystal, aromatic -stacking [centroid-centroid separations = 3.606 (5) and 3.671 (5) Å ] connect the molecules into stacks propagating in the [010] direction (Fig. 2).