(Dialkylamino)thiazole dimers act as very strong electron-donating coupling components in azo dyes, the first and second UV–VIS absorption bands of which were observed at λ = 568–737 (ε = 24000–88000) and 404–475 (ε = 9200–52000) nm in dichloromethane, respectively. The azo compounds derivedfrom the (dialkylamino)thiazole dimers having very strong electron-withdrawing moieties such as 4-(perfluoroalkylsulfonyl)phenyls
4-Substituted (perfluoroalkylsulfonyl)benzenes have been synthesized by the oxidation of 4-substituted (perfluoroalkylthio)benzenes with hydrogen peroxide, anhydrous chromic oxide and potassiumpermanganate in good yields. 4-(Perfluoroalkylsulfonyl) anilines have been also prepared by the reduction of the corresponding nitrobenzenes.