Preparation, crystal structure, luminescence and Hirshfeld surface of hydroxynaphthene-based compounds.

• Butyl 1‑hydroxy-2-naphthoate have been obtained. • The crystal structures were characterized by single crystal X–ray diffraction. • The melting point and the emission peaks can be modulated by the substitute. • The luminescent maxima are relative to the close contacts of C···C. To explore the new luminescent materials, two compounds based on hydroxynaphthene group have been prepared. Compound 2 was synthesized through the esterification of compound 1 in the acid conditions. They have been characterized by IR, EA and single crystal X-ray diffraction. Single X-ray diffraction reveals that compounds 1 and 2 belong to the P 2 1 / n and P 2 1 / c , respectively. It is obviously observed that there exist C/O H⋯O and the packing interactions among the aromatic rings. The solid-state fluorescent spectra reveal that the maxima of compounds 1 and 2 are 448 and 415 nm, respectively. The luminescent emission maxima are in accordance with the stacking interactions of compounds. The melting points of both compounds can be found to be 190–192 °C and 78–80 °C, respectively. The Hirshfeld surface analysis further reveals that the close contacts C⋯C are responsible for the luminescent peaks, and the O⋯H/H⋯O close bonds can account for the melting points of both compounds. Two compounds based on hydroxynaphthene group have been prepared, which have been characterized by IR, EA and single crystal X-ray diffraction. The fluorescence maxima of compounds 1 and 2 are 448 and 415 nm, respectively. The melting point of both compounds 190–191 °C and 78–80 °C, respectively. The Hirshfeld surface analysis further confirm that the close contacts C⋯C are responsible for the luminescent peaks, and the O⋯H/H⋯O close bonds can account for the melting points of both compounds. [Display omitted] [ABSTRACT FROM AUTHOR]