POSSIBLE REACTION PATHWAYS FOR THE FORMATION OF 3-CHLORO-4-(DICHLOROMETHYL)-5-HYDROXY-2(5H)-FURANONE (MX).

Article abstract of DOI:10.1016/0045-6535(94)90329-8

Three compounds, 3,4,5-trimethoxybenzaldehyde (I), 1-dichloromethyl-3,4,5-trimethoxy-benzene (II) and 3,4,5-trimethoxyphenylacetic acid (III) were treated with aqueous chlorine at pH 2. Aqueous chlorination of the three compounds increased the formation of MX (3-chloro-4-dichloromethyl-5(2H)-hydroxyfuranone) and E-MX (E 2-chloro-3-dichloromethyl-4-oxo-butenoic acid) in the order I>II>III. By ¹H-NMR spectroscopy and gas chromatography it was shown that II hydrolizes readily to I in water. It is known that III is converted to II in chlorination reactions. We suggest that the (formed) aldehyde group remains intact during the formation of MX and E-MX from these three compounds. They could thus form MX and E-MX, via similar mechanisms. This suggested mechanism may also occur when phenolic precursor structures present in humic material are treated with chlorine in the process of drinking water production.