2-Methyl-4-(4-nitrophenyl)but-3-yn-2-ol: crystal structure, Hirshfeld surface analysis and computational chemistry study

The di-substituted acetylene residue in the title compound, C11H11NO3, is capped at either end by di-methylhydroxy and 4-nitrobenzene groups; the nitro substituent is close to co-planar with the ring to which it is attached [dihedral angle = 9.4 (3)degrees]. The most prominent feature of the molecular packing is the formation, via hydroxy-O-H center dot center dot center dot O(hydroxy) hydrogen bonds, of hexameric clusters about a site of symmetry (3) over bar. The aggregates are sustained by 12-membered {center dot center dot center dot OH}(6) synthons and have the shape of a flattened chair. The clusters are connected into a three-dimensional architecture by benzene-C-H center dot center dot center dot O(nitro) interactions, involving both nitro-O atoms. The aforementioned interactions are readily identified in the calculated Hirshfeld surface. Computational chemistry indicates there is a significant energy, primarily electrostatic in nature, associated with the hydroxy-O-H center dot center dot center dot O(hydroxy) hydrogen bonds. Dispersion forces are more important in the other identified but, weaker intermolecular contacts.