Oxygenation by Superoxide Ion of 1,2-Dibromo-1,2-diphenylethane, 2,3-Dibromobutane, Ethylene Dibromide (EDB), and 1,2-Dibromo-3-chloropropane (DBCP)

Article abstract of DOI:10.1021/ja00335a053

In dimethylformamide (DMF) superoxide ion (O2^-.) reacts with PhCHBrCHBrPh, MeCHBrCHBrMe, and CH2BrCH2Br (EDB) via 2:1 stoichiometry to produce PhCH(O), MeCH(O), and CH2(O), respectively.A similar oxygenation occurs when O2^-. and CH2BrCHBrCH2Cl (DBCP) are combined in 5:1 stoichiometry to yield two CH2(O) and one HOC(O)O^- per substrate.The relative rates of reaction are in the order CH2BrCH2 > PhCHBrCHBrPh > MeCHBrCHBrMe.On the basis of the reaction rates and the products, the initial step for each substrate is believed to be a nucleophilic attack on a bromo carbon (R2CHBr) with displacement of Br^- and formation of R2CHOO^..Subsequent steps involve reduction by a second O2^-. and a dioxetane closing on an adjacent C-X group.