FRIES REACTION AND DAKIN REARRANGEMENT IN BENZO-2,1,3-THIADIAZOLES

Article abstract of DOI:10.1007/BF00472265

The Fries rearrangement of 4- and 5-acetoxybenzo-2,1,3-thiadiazoles has given 4-hydroxy-7-acetyl- and 5-hydroxy-4-acetylbenzo-2,1,3-thiadiazoles, which on oxidation afford mixtures of 5-chloro-4,7-dioxo- and 5,6-dichloro-4,7-dioxobenzo-2,1,3-thiadiazole and of 6-chloro-4,5-dioxo- and 6,7-dichloro-4,5-dioxobenzo-2,1,3-thiadiazole.Reaction of 6,7-dichloro-4,5-dioxobenzo-2,1,3-thiadiazole with ortho-phenylenediamine gives 4,5-dichloro-2,1,3-thiadiazolo<4,5-a>phenazine.