Et3N (0.105 mL, 0.751 mmol) and TBSOTf (0.146 mL, 0.635 mmol) were sequentially added (TBSOTf: dropwise, over 2 min) to a solution of 1-(3-methyl-2-phenoxyquinolin-8-yl)ethanone (160.1 mg, 0.577 mmol) in DCM (3.0 mL) at 0° C., and the resulting was stirred at 0° C. for 30 min. The mixture was partitioned between DCM (50 mL) and saturated aq. NaHCO3 (20 mL). The organic layer was separated, and the aq. layer was extracted with DCM (2×20 mL). The combined organic extracts were then dried over Na2SO4, filtered, and concentrated in vacuo to provide 8-(1-((tert-butyldimethylsilyl)oxy)vinyl)-3-methyl-2-phenoxy quinoline (214.0 mg, 0.547 mmol, 95% yield) as a colorless oil. This material was taken up in THF (3.0 mL), water (0.166 mL, 9.24 mmol) and NBS (103 mg, 0.577 mmol) were sequentially added at 25° C., and the resulting solution was stirred at 25° C. for 15 min. The mixture was partitioned between Et2O (50 mL) and water (30 mL). The organic layer was separated, sequentially washed with saturated aq. NaHCO3 (20 mL), water (20 mL), and brine (20 mL), and then dried over MgSO4, filtered, and concentrated in vacuo to provide 2-bromo-1-(3-methyl-2-phenoxyquinolin-8-yl)ethanone (240 mg) as a light-yellow oil: m/z (ESI, +ve) 356.0 (M+H)+. NH4OAc (178 mg, 2.309 mmol) and piperidine-2,4-dione (78 mg, 0.693 mmol) were added to the resulting oil, and the mixture was taken up in EtOH (3.0 mL) and stirred at 25° C. for 5 min. The reaction vial was sealed under argon and heated at 50° C. for 14.5 h. The mixture was cooled to 25° C. and concentrated in vacuo. The residue was partitioned between DCM (50 mL) and saturated aq. NaHCO3 (30 mL). The aq. layer was extracted with DCM (3×30 mL), and the combined extracts were dried over Na2SO4, filtered, and concentrated in vacuo. Chromatographic purification of the residue (silica gel, 0-10% MeOH/DCM) furnished 2-(3-methyl-2-phenoxyquinolin-8-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one (53.4 mg, 0.145 mmol, 25% yield) as a yellow solid: 1H NMR (400 MHz, CDCl3) δ ppm 11.28 (1H, br. s.), 7.92-8.00 (2H, m), 7.50-7.58 (3H, m), 7.34-7.43 (2H, m), 7.29 (2H, d, J=7.8 Hz), 7.08 (1H, d, J=1.8 Hz), 5.36 (1H, br. s.), 3.50 (2H, t, J=6.7 Hz), 2.56 (3H, s), 2.42 (2H, t, J=6.9 Hz). m/z (ESI, +ve) 370.1 (M+H)+.
