Investigation of nicotinamide and isonicotinamide derivatives: A quantitative and qualitative structural analysis

An anhydrous nature of benzylidene derivatives of nicotin and isonicotinamides crystal structures is determined and studied for their weak intermolecular interactions. The molecular structure is non-planar in general with the pyridine ring twisted with respect to the central hydrazone moiety. The crystal structures depict various intermolecular interactions, including N–H⋯O, C–H⋯O, N–H⋯N, and C–H⋯N hydrogen bonding along with weak C–H … π and π … π contacts. Further, Hirshfeld surface and 2D-fingerprint plot analysis confirm the role of intermolecular interactions in building the crystal packing in these derivatives. The PIXELC energy calculation shows that dispersion energy plays an essential role in stabilizing the crystal packing in all six derivatives.