Collect. Czech. Chem. Commun. 1986, 51, 2802-2809

Some nucleophilic reactions of 2-isothiocyanatobenzyl bromide. A new simple synthesis of 2-substituted 4H-benzo[d][1,3]thiazines

Jozef Gonda and Pavol Kristian

Department of Organic Chemistry and Biochemistry, faculty of Natural Sciences, P. J. Šafárik University, 041 67 Košice


N-Bromosuccinimide reacts with o-tolyl isothiocyanate to afford 2-isothiocyanatobenzyl bromide, a new type of bifunctional synthon. Nucleophiles I-, SCN-, 4-CH3C6H4SO2- and hexamethylenetetramine yield substitution products of bromine. Amines and phenols react exclusively with the NCS grouping under formation of unstable thioureas, which in turn cyclize to the corresponding 4H-benzo[d][1,3]thiazines. Structure of these compounds was corroborated by IR, 1H, 13C NMR and mass spectral data and backed by elemental analysis.