Abstract

FERNANDEZ, Lenys; MARQUEZ, Olga P; MARQUEZ, Jairo  and  VELASQUEZ, William. Electrochemical chlorination of phenylnonane. Rev. Téc. Ing. Univ. Zulia [online]. 2002, vol.25, n.2, pp.108-117. ISSN 0254-0770.

By using phase transference catalysis, anodic chlorination of phenylnonane in a two immiscible liquids (dichloromethane-water) with tetrabutylammonium as the transference agent; pchlorononylbenzene was obtained as the main product with an organic yield of 47%, which means an improvement compared with 24% obtained when using a single solvent. Formation of p-chlorononylbenzene depends upon the nature and concentration of the transference agent, pH, temperature, and oxidation potential. The best conditions were reached using 0.3M Bu₄NHSO₄, at a pH ranging within 4 and 6, at 35°C and 1.70 V vs Ag/Ag⁺. Our results suggest that at those potentials below the oxidation peak of the aromatic, the formation of the chlorinated species is due to a chemical reaction between the electrochemically generated chlorinating species and the neutral molecule of phenylnonane. On the other hand, at those potentials above the oxidation peak, the reaction occurs between the chlorinating species and a cationic species generated by oxidation of phenylnonane. To confirm our results, experiments were run in acetonitrile-water, showing that at low potentials (~1.40 V vs Ag/Ag⁺), 20% of p-chlorononylbenzene is formed by direct reaction between the chlorinating species and the phenylnonane while at higher potentials, 27% of p-chlorononylbenzene and 34% of nonylacetamide is produced by reaction of the chlorinating species and the electrolytic medium with the organic cationic intermediate species.

Keywords : Hydrocarbons fictionalization; anodic oxidation; electrochemical chlorination; phenylnonane.