Study of halogen interactions in dichlorovinyldiazenes: Structural analysis, DFT simulation and molecular modeling

In recent years, our research group has synthesized about two hundred different dihalogenated vinyldiazenes. The analysis revealed that the type (conformation) of the compounds is the same-"bike stop", but the properties and nature of intermolecular interactions are different. The concepts of the nature of halogen-halogen relationships recommended by IUPAC (2013) do not explain the nature of the observed intermolecular interactions in the synthesized systems. In this paper, for the first time, using the examples of the compounds presented below, an algorithm is built for the relationship between the structure of synthesized compounds and their properties, and the nature of non-covalent interactions involving the chlorine atom.

The molecules presented in this paper were studied by the DFT method using the hybrid potential of B3LYP with the Gaussian 09 software package. The extended basis 6-311++G(d,p) with polarization and diffusion functions was used for calculations. Conducted NBO analysis of atomic charge populations. Calculations of the structural parameters of the synthesized systems were carried out in order to study the reactivity, molecular properties and identify the nature of non-covalent interactions involving the halogen atom. It has been established that the Cl–C–Cl triad has a flat geometry and is capable of forming atypical non-covalent interactions both with each other and with various coplanar systems.