(Z)-3-(4-(Dimethylamino)benzylidene)thiochroman-4-one: Synthesis, Crystal Structure and Molecular Modelling Using Density Functional Theory

The title compound C18H17NOS was synthesized by condensation of thiochroman-4-one with 4-dimethylaminobenzaldehyde. The possible existence of the 3-(4-(Dimethylamino)benzylidene)thiochroman-4-one (E)- and (Z)-geometrical isomers was investigated using B3LYP/6-31G**. Crystallographic and vibrational data are compared with the results of Density Functional Theory (DFT) B3LYP/6-31G** level. Bond orders were estimated using the NBO calculation method correlating with changes in the bond length. To explain deviation of an ideal molecular geometry, the concept of non-equivalent hybrid orbitals was invoked. The studies of X-ray diffraction revealed strong intermolecular interactions between dimers of the compound connected to each other through dipole-dipole interactions S-C, N-C y O-C in the absence of hydrogen bonding.Graphical AbstractIn this report, a study of the structural characterization of (Z)-3-(4-(dimethylamino)benzyliden)thiochroman-4-one is carried out by spectroscopic methods, single-crystal X-ray diffraction and functional density calculations.