OXIDATIVE CYCLIZATION OF HALOBENZOPHENONE OXIMES TO 4,2'-IODONIA-3-PHENYL-1,2-BENZISOXAZOLE SALTS

Article abstract of DOI:10.1007/BF00504396

It is shown that the syn oximes of o-iodo- and o-, m-, and p-bromobenzophenones, under the influence of K2S2O8 in concentrated H2SO4, form the corresponding 3-aryl-1,2-benzisoxazoles as a result of oxidative cyclization. 3-(2-Iodophenyl)-1,2-benzisoxazole is oxidized by peracetic acid to the iodoso derivative which, upon heating in concentrated H2SO4, undergoes cyclization to the 4,2'-iodonia-3-phenyl-1,2-benzisoxazole cation.The iodide, bromide, and tetrafluoroborate of this cation were isolated.