250122-02-2Relevant academic research and scientific papers
An "on-water" exploration of CuO nanoparticle catalysed synthesis of 2-aminobenzothiazoles
Rout, Saroj Kumar,Guin, Srimanta,Nath, Jayashree,Patel, Bhisma K.
, p. 2491 - 2498 (2013/02/21)
An "on-water" one-pot process has been engineered for the preparation of 2-aminobenzothiazole from ortho-halo (-F, -Cl, -Br and -I) substituted unsymmetrical thioureas. For ortho -I and -Br substrates the reactions afford 2-aminobenzothiazoles under metal free condition promoted by base. However, the relatively inert ortho -Cl and -F substrates undergo intramolecular arylthiolation only in the presence of CuO nanoparticles yielding 2-aminobenzothiazoles. This methodology provides easy access to aminobenzothiazoles utilising even the ortho -Cl and -F substrates. The catalyst is recyclable several times without loss of substantial activity. Other remarkable features include the wide range of functional group tolerance, absence of chromatographic purification (for ortho -I and -Br substrates) and providing moderate to excellent yield of the products under mild conditions, thus rendering the methodology as a highly eco-friendly alternative to the existing methods.
Direct transition metal-free C-S bond formation: Synthesis of 2-aminobenzothiazole derivatives via base-mediated approach
Wang, Rui,Chen, Zhi,Yue, Liang,Pan, Wei,Zhao, Jun-Jie
experimental part, p. 4529 - 4531 (2012/09/22)
A general, efficient, and more practical protocol for the base-mediated intermolecular or intramolecular S-arylation leading to the 2-aminobenzothiazole derivatives is reported. Remarkably, all reactions were carried out under transition-metal-free conditions with good to excellent yields, rendering the methodology presented herein highly valuable from both environmental and economic points of view.
