Isoquinoline (III) was prepared by the condensation of piperonal N-propylimine (I) with 4,5-dimethoxyhomophthalic anhydride (II). Subsequent intramolecular Friedel-Crafts acylation of (III) in the presence of Eaton's reagent gave rise to the indenoisoquinoline (IV). Reduction of the ketone and lactam functions of (IV) using borane-tetrahydrofuran complex provided alcohol (V). This underwent simultaneous dehydration and dehydrogenation in the presence of Pd/C in refluxing HOAc to afford, after treatment with NaCl, the target indenoisoquinolinium chloride salt.