Transformation of 3-(3-arylalkylcarbamoyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-1-yl)propanenitriles into amides and acids

A mixture of hydrochloric and acetic acids depleted in water was proposed to effect stepwise transformation of 3-(3-arylalkylcarbamoyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-1-yl)propanenitriles into the corresponding amides and then into the acids. The procedure turned out to be efficient with 3-(2-phenylethyl)-carbamoyl] derivatives, whereas the reactions with benzylcarbamoyl analogs were accompanied by partial or complete debenzylation.