On the importance of intermolecular interactions of 3-(2,3-dihydroxy-isopentyl)-4-hydroxyacetophenone: Crystal structure, spectroscopic and hirshfeld surface analysis

Abstract The compound 3-(2,3-dihydroxy-isopentyl)-4-hydroxyacetophenone has been synthesized and characterized by 1H Nuclear Magnetic Resonance (NMR), Infrared (IR) and Raman spectroscopies and its crystal structure was solved by single crystal X-ray diffraction. The molecular geometry of the compound was investigated theoretically by performing density functional theory (DFT) calculations to access reliable results to the experimental data. The substance crystallizes in the triclinic P 1 ¯ crystal system with Z = 2 molecules per unit cell. The crystal structure of the compound shows the two methyl groups attached to the C11 atom are in a gauche conformation in relation to the C9 methylene group which in turn is antiperiplanar with respect to the C11 hydroxyl group. A similar disposition was observed for the C13 methyl group in relation to the C10 hydroxyl group. The most stable conformer obtained by conformational analysis shows the O3–H3 and O4–H4 hydroxyl groups in an anti-conformation. The differences observed between experimental and calculated results were interpreted in terms of intermolecular interactions in the crystal packing. The structure reveals that the crystal packing is governed by O–H⋯O hydrogen bonding and weak C–H⋯O and C–H···π non-covalent interactions. A detailed analysis of Hirshfeld surfaces and their associated 2D fingerprint plots allowed quantifying the interactions within the crystal structures.