To a solution of 2-Methyl-4-oxo-3,4-dihydro-2H-quinoline-1-carboxylic acid benzyl ester (1.00 g, 3.39 mmol), triethylamine (3.77 mL, 27.1 mmol) in dichloromethane (10 ml), cooled at 0° C. in an ice/sodium chloride bath, a solution of titanium tetrachloride in toluene (3.39 mL, 1.0 M in toluene) was dropwise added for 10 minutes. Benzyl amine (0.74 mL, 3.39 mmol) was added and the mixture was stirred over night at room temperature. The reaction was quenched with saturated NaHCO3 solution (100 mL) and the mixture was extracted with ethyl acetate (3×200 mL). The combined organic layers were washed with brine (200 mL), dried (Na2SO4), filtered and concentrated to give a reddish oil (1.70 g) which was used directly in the next step.
