Synthesis of Sulfones in the Pyrrolo[2,1-b]thiazole Series

(Arylsulfonyl)acetonitriles were shown to react with mercaptoacetic acid in refluxing pyridine yielding 2-[(arylsulfonyl)methylidene]thiazolidin-4-ones. The latter underwent alkylation with α-bromoketones in the presence of K₂CO₃ selectively at the nitrogen atom. Further formylation of the resulting phenacyl derivatives with excess DMF•POCl₃ complex afforded 5-aroyl-7-arylsulfonyl-2-[(dimethylamino)methylidene]pyrrolo[2,1-b]thiazol-3(2H)-ones.

Tverdokhlebov A. V.; Andrushko A. P.; Tolmachev A. A.
Synthesis 2006, 09, 1433-1436
DOI: 10.1055/s-2006-926438