The weak intermolecular interactions in 2,6-Bis(4-Isopropylbenzylidene) Cyclohexanone : insights from crystallographic studies and semi-empirical quantum chemical calculations

Abstract

In the molecular structure of 2,6-bis(4-isopropylbenzylidene) cyclohexanone, (I), the central cyclohexane ring adopts half-chair conformation quantified by ring puckering analysis and asymmetry parameters. The olefinic double bonds in the title compound have E-conformation. The conformational discrepancy between the experimental structure and theoretical one computed by AM1 semi-empirical method describes the role of short intramolecular C-H…O contacts and a weak C-H ……interaction in the solid state of a molecule. The parametric molecular electrostatic potential (PMEP) calculated by semi-empirical method also shows the involvement of oxygen atom in the short intramolecular C-H… O contacts in crystal packing. The intramolecular charge transfer resulting from HOMO-LUMO transition reflects the chemical activity of a molecule.