Metal-free synthesis of 2-substituted (N, O, C) benzothiazoles via an intramolecular C-S bond formation was written by Feng, Enguang;Huang, He;Zhou, Yu;Ye, Deju;Jiang, Hualiang;Liu, Hong. And the article was included in Journal of Combinatorial Chemistry in 2010.Formula: C13H10N2S This article mentions the following:
An efficient, economical, and convenient method was developed for the preparation of 2-substituted (N, O, C) benzothiazoles from N’-substituted-N-(2-halophenyl)thioureas, O’-substituted-N-(2-halophenyl) carbamothioates, or N-(2-halophenyl) thioamides via a base-promoted cyclization in dioxane without any transition metal. A one-pot variant combining the synthesis of the thiourea and the cyclization was also demonstrated. High yields were obtained, and a variety of functional groups were tolerated under these conditions. Transition-metal-free, mild reactive conditions, wide application scope, and shorter reaction times make this method superior to the reported methods for the synthesis of 2-substituted benzothiazoles and suitable for combinatorial format. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6Formula: C13H10N2S).
N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. The thiazole ring is notable as a component of the vitamin thiamine (B1). The nitrogen in thiazole is sp2 hybridized and the lone pair of electrons localized on the nitrogen is less reactive due to increased aromatic character and decreased basicity. It is protonated and alkylated/acylated at nitrogen forming hydrochloride and quaternary thiazolium salt.Formula: C13H10N2S
Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica