Selenium heterocycles XLIV. Syntheses of 8,9-dihydro-1,2,3-thiadiazolo 4,5-a -4,7-dihydroxynaphthalene and 1,2,3-selenadiazolo 4,5-a -4,7-dimethoxynaphthalene

Journal of Heterocyclic Chemistry

Volume 5 - Number

Article Type: ---- Unspecified ----
Abstract:

The reaction of thionyl chloride with the semicarbazone 2 gave 4,5-dihydro-6,9-dihydroxynaphtho[1,2-d][1,2,3]thiadiazole (3) instead of 4,5-dihydro-6,9-dimethyoxynaphtho[1,2-d][1,2,3]thiadiazole (4). Selenium dioxide oxidation of compound 2 gave 4,5-dihydro-6,9-dimethyoxynaphtho[1,2-d][1,2,3]selenadiazole (5). Oxidation of compound 5 with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone afforded 6,9-dimethyoxynaphtho[1,2-d][1,2,3]selenadiazole (6).