
%0 Journal Article
%A Chapman, KJ 
%A Dyall, LK 
%A Frith, LK 
%T Oxidative cyclizations. VI. Mechanism of cyclization of N-chloro-2-nitroanilines to benzofuroxans under alkaline conditions
%J Australian Journal of Chemistry
%D 1984/02/01
%V 37
%N 2
%P 341-354
%K 
%R https://doi.org/10.1071/CH9840341
%U https://www.publish.csiro.au/paper/CH9840341 
%X An improved synthesis of N-chloro-2-nitroanilines used chlorine in CCl4 solution to halogenate the 2-nitroaniline. Treatment of these CCl4 solutions of the N-chloroamines with methanolic lithium methoxide, or potassium t-butoxide in t-butyl alcohol, produced a transient red colour, and quantitative yields of the corresponding benzofuroxan (benzofurazan 1-oxide) were obtained. U.v. and e.s.r. spectra indicated that the red species is the conjugate base of the N-chloroamine. On the basis of rate measurements, it is concluded that this red anion ejects chloride ion irreversibly to yield a singlet ortho-nitrophenylnitrene, which then rapidly cyclizes to the benzofuroxan. The ortho-nitro group does not assist in chloride ion ejection. 
