479500-92-0Relevant articles and documents
Reduction of 1-(2-Chloroethyl)-2-nitrobenzene and 1-(2-Bromoethyl)-2- nitrobenzene at carbon cathodes: Electrosynthetic routes to 1-nitro-2- vinylbenzene and 1H -indole
Du, Peng,Peters, Dennis G.
experimental part, p. F167-F172 (2010/11/21)
Studies of the electrochemical reductions of 1-(2-chloroethyl)-2- nitrobenzene (1) and 1-(2-bromoethyl)-2-nitrobenzene (2) at carbon cathodes in dimethylformamide (DMF) containing tetramethylammonium tetrafluoroborate (TMABF4) have been undertaken. Cyclic voltammograms for 1 and 2 exhibit three irreversible cathodic peaks, the first of which is attributed to one-electron reduction of the nitro group, and the resulting nitro radical-anion immediately reacts as a base with the adjacent alkyl halide moiety via an E2 elimination to produce 1-nitro-2-vinylbenzene. At a potential corresponding to the first cathodic peak, bulk electrolyses of 1 or 2 in the absence of a proton donor afford 1-nitro-2-vinylbenzene as principal product, along with 1H -indole and a dimeric species. However, when 1 or 2 is electrolyzed in the presence of either phenol or 2,4-pentanedione as a proton source, the only significant product is 1H -indole. A mechanistic picture for the reductions of 1 and 2 is proposed, and a separate examination of the electrochemical behavior of 1-nitro-2-vinylbenzene has been included as part of this work.
