406927-44-4Relevant 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.
Arylthioureas with bromine or its equivalents gives no 'Hugerschoff' reaction product
Yella, Ramesh,Murru, Siva,Ali, Abdur Rezzak,Patel, Bhisma K.
experimental part, p. 3389 - 3393 (2010/08/22)
The in situ generated aryl-alkyl unsymmetrical thiourea obtained by the reaction of an aryl isothiocyanate with an aliphatic secondary amine on treatment with bromine or its equivalent gave exclusively a product having a thioamido guanidino moiety and not the expected Hugerschoff product 2-aminobenzothiazole. A plausible reaction mechanism has been proposed for this unprecedented transformation and the scope has been extended to various substrates. The Royal Society of Chemistry 2010.
