Elizabeth Alina Przybylski

Exhaustive liquid-phase catalytic hydrodehalogenation of chlorobenzenes

Abstract The exhaustive hydrodehalogenation reactions of chlorobenzenes bearing up to four halogen atoms have been studied in ethanol. At near-ambient temperatures and several atmospheres hydrogen pressure, only a palladium on carbon catalyst exhibited measurable activity. Reaction pathways were determined for chlorobenzene, all of the dichloro- and trichloro-isomers, and 1,2,4,5-tetrachlorobenzene. Use of ammonia as a proton acceptor in combination with the palladium catalyst enabled complete dechlorination to product benzene at a usefully rapid rate at room temperature and modest pressure.