Palladium-catalyzed amination of 2-chlorothienopyridone with primary aromatic amines

Abstract A series of ethyl 7-cyclopropyl-2-(arylamino)-3-nitro-4-oxo-4,7-dihydrothieno[2,3-b]pyridine-5-carboxylate (9a-d) were prepared by coupling of ethyl 7-cyclopropyl-2-chloro-3-nitro-4-oxo-4,7-dihydrothieno[2,3-b]pyridine-5-carboxylate (8) with primary aromatic amines via palladium-catalyzed amination using palladium acetate Pd(OAc)2 in the presence of cesium fluoride in good yields. The new compounds were characterized by 1H-NMR, 13C-NMR, mass spectrometry, high resolution mass spectrometry and elemental analysis. 7-cyclopropyl-2-(phenylamino)-3-nitro-4-oxo-4,7-dihydrothieno[2,3-b]pyridine-5-carboxylic acid (10a) showed weak activity against E.aerogenas and S.aureus bacteria.