Microperoxidase/H2O2-mediated alkoxylating dehalogenation of halophenol derivatives in alcoholic media.
The results of this study report the H2O2-driven microperoxidase-8 (MP8)-catalyzed dehalogenation of halophenols such as 4-fluorophenol, 4-chlorophenol, 4-bromophenol, and 2-fluorophenol in alcoholic solvents. In methanol, the conversion of the para-halophenols and 2-fluorophenol to, respectively, 4-methoxyphenol and 2-methoxyphenol, as the major dehalogenated products is observed. In ethanol, 4-ethoxyphenol is the principal dehalogenated product formed from 4-fluorophenol. Two mechanisms are suggested for this MP8-dependent alkoxylating dehalogenation reaction. In one of these mechanisms the oxene resonant form of compound I of MP8 is suggested to react with methanol forming a cofactor-peroxide-alkyl intermediate. This intermediate reacts with the reactive pi-electrons of the substrate, leading to the formation of the alkoxyphenols and the release of the fluorine substituent as fluoride anion.
Osman
A M
AM
Department of Biochemistry, Agricultural University, Dreijenlaan 3, 6703 HA, Wageningen, The Netherlands.
Boeren
S
S
Boersma
M G
MG
Veeger
C
C
Rietjens
I M
IM
D002733:Chlorophenols / Q000378:metabolism*; D000431:Ethanol; D008401:Gas Chromatography-Mass Spectrometry; D006219:Halogens / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D000432:Methanol; D008956:Models, Chemical; D010544:Peroxidases / Q000378:metabolism*; D010636:Phenols / Q000378:metabolism*; D012997:Solvents
D002733:Chlorophenols; D006219:Halogens; D010636:Phenols; D012997:Solvents; D000431:Ethanol; D006861:Hydrogen Peroxide; D010544:Peroxidases; C021799:microperoxidase; D000432:Methanol