Ethyl 1-cyano-6-mesityl-4-oxo-4H-quinolizine-3-carboxylate (0.110 g, 0.30 mmol) was dissolved in 20 mL ethanol and HCl (0.15 mL) and treated with 20% Pd(OH)2 over charcoal (0.050 g). The solution was evacuated and filled with a hydrogen balloon. After 5 h, the solution was filtered and concentrated to give a yellow solid. The hydrochloride salt was then dissolved in 1,2-dichloroethane (5 mL) and propionaldehyde (0.078 mL, 1.1 mmol) was added followed by sodium triacetoxyborohydride (0.23 g, 1.1 mmol). The reaction was heated to 40° C. overnight. The solution was cooled, quenched with water. Extraction with ethyl acetate was followed by drying the organic layer, concentration, and flash chromatography (ethyl acetate) to give 0.059 g (42% yield) of the title compound.
