title: Synthesis, molecular structure, and applications of 2-hydroxylamino-4,5-dihydroimidazolium-O-sulfonate to the synthesis of novel heterocyclic ring systems.
abstract: 2-hydroxylamino-4,5-dihydroimidazolium-O-sulfonate (1) has been prepared by reacting 2-chloro-4,5-dihydroimidazole with hydroxylamine-O-sulfonic acid. Deprotonated compound 1a containing both the nucleophilic endocyclic nitrogen atoms and electrophilic exocyclic nitrogen was used for the syntheses of 3-substituted 6,7-dihydro-5H-imidazo[2,1-c][1,2,4]oxadiazoles 2-9 and 6,7-dihydro-5H-imidazo[2,1-c][1,2,4]thiadiazole-3-thione (10) by tandem nucleophilic addition-electrophilic amination reaction. The method promises utility in the synthesis of a variety of other heterocycles. On the other hand, the convenient routes to 7,8-dihydroimidazo[1,2-c][1,3,5]thiadiazine-2,4(6H)-dithione (16) and 2,6,7,8-tetrahydroimidazo[1,2-a][1,3,5]triazine-4(3H)-thione derivative (17) are reported starting from compound 1. The structures of the compounds prepared were established by elemental analyses, IR, NMR, and MS spectra, and in some instances X-ray analyses.
authors.affiliation: Department of Chemical Technology of Drugs, Medical University of Gdańsk, 80-416 Gdańsk, Poland. saczew@amg.gda.pl
authors.forename: Franciszek
authors.initials: F
authors.lastname: Saczewski
authors.forename: Jarosław
authors.initials: J
authors.lastname: Saczewski
authors.forename: Maria
authors.initials: M
authors.lastname: Gdaniec