Dehalogenation of aromatic halides using metallic calcium in ethanol.
The scope and limitations of the dehalogenation of aromatic halides 1 and 4a-p using metallic calcium in ethanol at room temperature were revealed. The cleavage of the carbon-chlorine bond on the aromatic ring bearing electron-donating group was difficult compared to the one bearing electron-withdrawing group. Moreover, we applied this method to the dechlorination of polychlorinated biphenyls (PCBs) in transformer oil. It was also found that the dechlorination took place easily under mild conditions. The existence of PCBs residue in the reaction at room temperature was less than 0.04% according to the GC-MS analysis. The chlorine was identified as calcium chloride.
Mitoma
Y
Y
Tohwa Institute for Science, and Department of Industrial Chemistry, Faculty of Engineering, Tohwa University, Fukuoka, Japan. mitoma@tohwa-u.ac.jp
Nagashima
S
S
Simion
C
C
Simion
A M
AM
Yamada
T
T
Mimura
K
K
Ishimoto
K
K
Tashiro
M
M
D002118:Calcium / Q000737:chemistry*; D004785:Environmental Pollutants / Q000032:analysis*; D000431:Ethanol / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006219:Halogens / Q000737:chemistry; D011078:Polychlorinated Biphenyls / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013696:Temperature
D004785:Environmental Pollutants; D006219:Halogens; D012997:Solvents; D000431:Ethanol; D011078:Polychlorinated Biphenyls; D002118:Calcium