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DOI: 10.1055/s-0029-1219122
Copper-Catalyzed Synthesis of 2-Amino-benzothiazoles
G. Shen, X. Lv, W. Bao*
Zhejiang University, P. R. of China
Publikationsverlauf
Publikationsdatum:
21. Januar 2010 (online)
Significance
The synthesis of N-substituted 2-aminobenzothiazoles by the copper(I)-catalyzed addition-cyclization reaction of 2-haloanilines and isothiocyanates is reported. The reaction is carried out under ligand-free conditions and the best results are obtained using CuI as a catalyst and K2CO3 as a base. The reaction proceeds well with electron-rich isothiocyanatobenzenes and in moderate yields with electron-deficient isothiocyanatobenzenes and benzoyl isothiocyanates. It is also successful with 2-bromoanilines and 2-bromopyridines. A mechanism involving a nucleophilic attack of the 2-haloaniline nitrogen onto the isothiocyanate followed by a ring closure under copper catalysis is proposed without evidence.