Molecular structure, DFT studies and Hirshfeld analysis of anthracenyl chalcone derivatives

Abstract

The molecular and crystal structure of two new chalcone derivatives, (E)-1-(anthracen-9-yl)-3-[4-(piperidin-1-yl)phenyl]prop-2-en-1-one, C28H25NO, (I), and (E)-1-(anthracen-9-yl)-3-[4-(diphenylamino)phenyl]prop-2-en-1-one, C35H25NO, (II), with the fused-ring system at the same position are described. In the crystals of (I) and (II), the molecules are linked via C-H O hydrogen bonds into inversion dimers, forming R 2 2(22) and R 2 2(14) ring motifs, respectively. Weak intermolecular C-H π interactions further help to stabilize the crystal structure, forming a two-dimensional architecture. The molecular structures are optimized using density functional theory (DFT) at B3LYP/6-311G++(d,p) level and compared with the experimental results. The smallest HOMO-LUMO energy gaps of (I) (exp. 2.76eV and DFT 3.40eV) and (II) (exp. 2.70eV and DFT 3.28eV) indicates the suitability of these crystals in optoelectronic applications. All intermolecular contacts and weaker contributions involved in the supramolecular stabilization are investigated using Hirshfeld surface analysis. The molecular electrostatic potential (MEP) further identifies the positive, negative and neutral electrostatic potential regions of the molecules.