Synthesis, characterization and DFT calculations of 4,5,12- and 1,8,12-trichloro-9,10-dihydro-9,10-ethanoanthracene-12-carbonitriles

Abstract

The chlorinated ethanoanthracenes: 4,5,12- and 1,8,12-(trichloro-9,10-dihydro-9,10-ethanoanthracene-12-carbonitriles) (1 and 2), which are regioisomers, were synthesized and characterized using nuclear magnetic resonance (1H- and 13C-NMR) and infrared (IR) spectroscopic techniques. The structure of isomer 1 was further confirmed using a single-crystal X-ray technique. The relative stabilities of the title compounds were calculated using the density functional theory (DFT) method on the basis of their total energies and thermodynamic parameters. Isomer 1 is thermodynamically more stable than isomer 2 in the gas phase and in solution. The calculated molecular geometry of isomer 1 agreed well with the experimental X-ray structure. The atomic charge distribution at the different atomic sites was calculated using natural bond orbital analysis. Isomer 2 was predicted to be more polar than isomer 1.