【Paper】
Selectivity in Dechlorination of Chlorobiphenyls and Chlorotoluenes
Yuji Ukisu* and Tatsuo Miyadera*
* National Institute of Advanced Industrial Science and Technology（AIST）
†Correspondence should be addressed to Yuji Ukisu:
（AIST Tsukuba West, 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569 Japan）


Abstract
In order to reveal the effect of substituents for dechlorination of chloro-aromatic compounds, dechlorination reactions of mono- and di-chloro isomers of chlorobiphenyls and chlorotoluenes were carried out in a solution of NaOH in 2-propanol with a carbon-supported palladium catalyst（Pd/C）at 40℃. In the dechlorination of chlorobiphenyls, chlorine at 2-（ortho-）position was less reactive than chlorine at 3-（meta-）and 4-（para-）positions, but chlorotoluenes exhibited no significant difference in dechlorination selectivity. The difference seems to arise from the steric effect of the substituents（phenyl and methyl）.


Key words: chlorobiphenyls, chlorotoluenes, dechlorination, selectivity, palladium catalyst