Water → HCID 89783869, compound

Participants

Reaction Steps

To a solution of 1-(2-chloro-7-fluoroquinolin-8-yl)ethanone (237 mg, 1.060 mmol) in 3 mL DCM at 0° C. was added Et3N (0.19 mL, 1.38 mmol) followed by TBSOTf (0.27 mL, 1.17 mmol dropwise). The reaction was stirred for 1 h, and was partitioned between saturated NaHCO3 and CH2Cl2. The aq. layer was extracted with CH2Cl2 (3×), and the crude material was concentrated to a yellow oil. The resulting oil was taken up in THF (6 mL), treated with water (0.31 mL, 16.9 mmol) and NBS (198 mg, 1.113 mmol). After 35 min, the mixture was partitioned between water and Et2O. The organic layer was sequentially washed with saturated NaHCO3, water, and saturated and NaCl, and then dried over anhydrous MgSO4, filtered, and concentrated in vacuo to give a yellow, viscous oil. This oil was treated with ammonium acetate (327 mg, 4.24 mmol) and piperidine-2,4-dione (144 mg, 1.272 mmol) and EtOH (6.0 mL) and stirred at RT for 5 min. The resulting yellow slurry was placed in a 50° C. bath for 16 h, cooled, and concentrated in vacuo. The crude residue was purified by silica gel chromatography (0-20% MeOH in DCM), affording 2-(2-chloro-7-fluoroquinolin-8-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one (84.8 mg, 0.269 mmol, 25.3% yield) as a orange solid: 1H NMR (400 MHz, MeOH-d4) δ ppm 8.29 (1H, d, J=8.6 Hz), 8.16 (1H, d, J=7.4 Hz), 7.75 (1H, d, J=11.7 Hz), 7.49 (1H, d, J=8.6 Hz), 7.15 (1H, d, J=3.7 Hz), 3.64 (2H, t, J=7.0 Hz), 3.03 (2H, t, J=7.0 Hz). 19F NMR (377 MHz, MeOH-d4) δ ppm −113.85 (1F, s). m/z (ESI, +ve ion) 316.1 (M+H)+. m/z (ESI, +ve ion) 316.1 (M+H)+.

Provenance & Evidence