Production of 9-thioxo-2,3,4,9-tetrahydro-pyrrolo[3,4-b]quinolin-1-one derivatives from the aminolysis of 3,3,9-trichloro-3H-thieno[3,4-b]quinolin-1- one

Treatment of the title substrate with propylamine yielded 2-propyl-9-propylamino-3-propylimino-2,3-dihydro-pyrrolo[3,4-b] quinolin-1-one (15%) and a S-containing product (63%). The latter is inferred (from its spectral and chemical properties) to be a (1:1) complex of 2-propyl-3- propylimino-9-thioxo-2,3,4,9-tetrahydro-pyrrolo[3,4-b]quinolin-1-one (derived via an unusual S-rearrangement) with propylamine. The propylamine in the complex is removed by acid or thermally to provide the aforementioned 9-thioxo component which structure was substantiated from a X-ray crystal analysis. Aminolysis of the title substrate with ethylamine afforded the analogous ethyl-substituted products.