Syntheses and X-ray crystal structures combined with conformational and Hirshfeld analyses of chalcones based on a cyclohexanone scaffold

Four chalcone structures based on cyclohexanone cores were presented. The structures of bis-benzylidenecyclohexanone analogs 3a-d were elucidated using spectrophotometric and single-crystal X-ray techniques. Compounds 3a, 3b, and 3d crystalized in the monoclinic crystal system with the space group P21/c. However, 3c crystalized in the orthorhombic system with the space group Pna21. A set of computational studies related to the structures were carried out. Using the B3LYP method and the 6-31G(d,p) basis set, the molecular structures of the studied dienones were optimized, followed by the evaluation of their electronic properties and UV–vis spectra. The bond distances and angles well-correlated with the experimental data. All the dienones were stabilized by C–H⋯O intramolecular H-bonding interactions. The presence of two Cl atoms at the ortho-position of each phenyl ring in 3c caused steric hinderance with the cyclohexanone ring, leading to the weakest H⋯O interactions among the studied compounds. The TD-DFT method was used to assign and explain the origin of the electronic spectra of the studied dienones. [Display omitted] •The manuscript involved to prepare of four chalcone based cyclohexanone moiety.•The synthesized compounds were assigned by X-ray single crystal.•Conformational analysis of the designed compounds were carried out.•Computational studies of the designed compound were investigated.