Salt and co-crystal formation from 2-(imidazol-1-yl)-1-phenylethanone and different acidic components

Four crystalline adducts derived from 2-(imidazol-1-yl)-1-phenylethanone and the acidic compounds (2,4,6-trinitrophenol, p-nitrobenzoic acid, m-nitrobenzoic acid, and 5-nitrosalicylic acid) were prepared and characterized by X-ray diffraction analysis, infrared spectrum, melting point, and elemental analysis. All supramolecular architectures of 1-4 involve extensive classical hydrogen bonds as well as other non-covalent interactions. The results presented herein indicate that the strength and directionality of the N-H center dot center dot center dot O, O-H center dot center dot center dot N, and O-H center dot center dot center dot O hydrogen bonds (ionic or neutral) between acidic components and 2-(imidazol-1-yl)-1-phenylethanone are sufficient to bring about the formation of binary organic acid-base adducts. (C) 2011 Elsevier B.V. All rights reserved.