DFT Analysis of Uncommon π···H-Bond Array Interaction in a New Pterostilbene/Theophylline Cocrystal
journal contributionposted on 02.09.2020, 12:33 authored by Lídia Bofill, Rafel Prohens, Rafael Barbas, Antonio Frontera
A new cocrystal formed between the nutraceutical compounds pterostilbene and theophylline was synthesized and X-ray characterized in the form of a dichloromethane solvate. An interesting supramolecular assembly is formed by means of a combination of common and uncomment π–π and H-bonding interactions. It was computationally studied by a combination of density functional theory (DFT), quantum theory of “atoms-in-molecules”, and noncovalent interaction plot approaches, and the analyses revealed a π(CC)···H-bond array interaction, which is the first description of this type of interaction where the donor π-system is a double bond. The participation of the cocrystallized CH2Cl2 solvent molecule in Cl···Cl and C–H···π interactions was also studied using DFT and Hirshfeld surface calculations. The Cambridge structural database was inspected to investigate whether the π···H-bond array interaction is common in other theophylline cocrystals. Other examples where the π-system of an aromatic ring or an amido group interact with the H-bond array were found in literature and further discussed herein.