MANNICH REACTION WITH ARYLAMINE AS THE AMINO-COMPONENT IV. SYNTHESIS OF β-ARYLAMINOKETONES USING ARYLAMINE HYDROCHLORIDE AND HETEROCYCLIC KETONE

In ethanolic-HCI solution, Manni(?)h reaction was carried out directly between arylamine hydrochloride, paraformaldehyde (or 37% aqueous formaldehyde solution) and 2-acetylthiophene or 2-aoetylfuran to form β-arylaminoketone. This is a new method for the direct synthesis of 3-arylamino-l-(2'-thienyl)propanone-[1] and 3-arylamino-l-(2'-furanyl)propanone-[1] through Mannich reaction. The reaction conditions were discussed. The structure of the Mannich base was deduced from the IR and ~1H NMR data. Mannich reaction of 2-acetylthiophene or 2-aoetylfuran with HCHO and arylamine proceed exclusively at the CH_3 group α to the carbonyl.