3,4-Di-2-pyridyl-1,2,5-oxadiazole and its perchlorate salt

Abstract

In 3,4-di-2-pyridyl-1,2,5-oxadiazole (dpo), C12H8N4O, each mol­ecule resides on a twofold axis and inter­acts with eight neighbours via four C—H⋯N and four C—H⋯O inter­actions to generate a three-dimensional hydrogen-bonded architecture. In the perchlorate analogue, 2-[3-(2-pyrid­yl)-1,2,5-oxadiazol-4-yl]pyridinium perchlorate, C12H9N4O+·ClO4− or [Hdpo]ClO4, the [Hdpo]+ cation is bisected by a crystallographic mirror plane, and the additional H atom in the cation is shared by the two pyridyl N atoms to form a symmetrical intra­molecular N⋯H⋯N hydrogen bond. The cations and perchlorate anions are linked through C—H⋯O hydrogen bonds and π–π stacking inter­actions to form one-dimensional tubes along the b-axis direction.