| Abstract: | A novel method has been developed for the synthesis of sulfonic acids of five-membered heterocycles containing two heteroatoms, with a solution of sulfur trioxide in 1,2-dichloroethane. High yields of the required products are obtained, under conditions which are mild in comparison with those used in earlier methods. The mechanism of sulfonation is discussed, and some azole·SO3 complexes have been obtained and described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1353–1359, October, 1987. |
