Combined experimental and theoretical approaches to the molecular structure of 4-(1-formylnaphthalen-2-yloxy)phthalonitrile

The novel compound 4-(1-formylnaphthalen-2-yloxy)phthalonitrile, C19H10N2O2, has been synthesized and characterized by IR, UV–vis, NMR and X-ray single-crystal determination. The title compound, is built up from two planar groups (naphthalen and phthalonitrile), with a dihedral angle of 64.10(4)° between them. The crystal structure is stabilized by weak C–H⋯O hydrogen-bond and π–π interactions. The structural and spectroscopic data of the compound in the ground state have been calculated using density functional theory (DFT) and Hartree–Fock (HF) with the 6-31G(d,p) basis set. The vibrational study was interpreted in terms of potential energy distribution (PED). The observed wave number in FT-IR spectra was analyzed and assigned to different normal modes of the molecule. Using the TD-DFT and TD-HF methods, electronic absorption spectra of the title compound were predicted and good agreement with the TD-DFT method and the experimental determination was found. Isotropic chemical shifts (13C and 1H NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. The HOMO and LUMO analyses were used to elucidate information regarding charge transfer within the molecule.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The crystal structure is stabilized by weak C–H⋯O hydrogen-bond and π–π interactions. ► The structural and spectroscopic data of the compound was calculated using DFT and HF methods. ► Electronic absorption spectra of the title compound were predicted and good agreement with the TD-DFT method. ► Isotropic chemical shifts (13C and 1H NMR) were calculated using the GIAO method.