Synfacts 2007(12): 1244-1244  
DOI: 10.1055/s-2007-991398
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart · New York

Palladium-Catalyzed Synthesis of Benzothiazoles Using a Thiol Surrogate

Contributor(s): Victor Snieckus, Jignesh J. Patel
T. Itoh*, T. Mase
Banyu Pharmaceutical Co. Ltd., Ibaraki, Japan
Further Information

Publication History

Publication Date:
22 November 2007 (online)


Reported here is a one-pot procedure for the synthesis of benzothiazoles from the reaction of 2-bromobenzanilides with 2-ethylhexyl 3-mercaptopropionate in presence of catalytic Pd2(dba)2/XantPhos. The mercaptopropionate is used as a thiol surrogate which is released from the coupled product by β-elimination for the final cyclization to benzothiazole. Neutral or electron-deficient carbonyl amides were easily cyclized under basic conditions. Anilides with EWGs and substrates with electron-rich carbonyl amides undergo effective cyclization under acidic conditions. (4-Methoxyphenyl)methanethiol may be used as an alternative thiol surrogate.