ethyl 6-chloro-2-oxohexanoate

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Ethyl 6-chloro-2-oxohexanoate (2.9 g, 15 mmol) in carbon tetrachloride (30 mL) was treated with bromine (0.85 mL, 16.5 mmol) and stirred at ambient temperature for 1 hour. The reaction mixture was diluted with EtOAc, washed with Na2S2O3 solution, water and brine, dried (MgSO4), filtered and concentrated under reduced pressure. The concentrate was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes to provide (95%) of the desired product ethyl 3-bromo-6-chloro-2-oxohexanoate (23A) as a pale yellow oil: 1H NMR (300 MHz, DMSO-d6) δ ppm 5.25 (1H, dd), 4.29 (2H, q), 3.71 (2H, t), 2.16 (1H, m), 1.91 (1H, m), 1.29 (3H, t). washed with Na2S2O3 solution, water and brine dried (MgSO4) filtered concentrated under reduced pressure The concentrate was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Ethyl 6-chloro-2-oxohexanoate (2.9 g, 15 mmol) in carbon tetrachloride (30 mL) was treated with bromine (0.85 mL, 16.5 mmol) and stirred at ambient temperature for 1 hour. The reaction mixture was diluted with EtOAc, washed with Na2S2O3 solution, water and brine, dried (MgSO4), filtered and concentrated under reduced pressure. The concentrate was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes to provide (95%) of the desired product ethyl 3-bromo-6-chloro-2-oxohexanoate (23A) as a pale yellow oil: 1H NMR (300 MHz, DMSO-d6) δ ppm 5.25 (1H, dd), 4.29 (2H, q), 3.71 (2H, t), 2.16 (1H, m), 1.91 (1H, m), 1.29 (3H, t). washed with Na2S2O3 solution, water and brine dried (MgSO4) filtered concentrated under reduced pressure The concentrate was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Ethyl 6-chloro-2-oxohexanoate (2.9 g, 15 mmol) in carbon tetrachloride (30 mL) was treated with bromine (0.85 mL, 16.5 mmol) and stirred at ambient temperature for 1 hour. The reaction mixture was diluted with EtOAc, washed with Na2S2O3 solution, water and brine, dried (MgSO4), filtered and concentrated under reduced pressure. The concentrate was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes to provide (95%) of the desired product ethyl 3-bromo-6-chloro-2-oxohexanoate (23A) as a pale yellow oil: 1H NMR (300 MHz, DMSO-d6) δ ppm 5.25 (1H, dd), 4.29 (2H, q), 3.71 (2H, t), 2.16 (1H, m), 1.91 (1H, m), 1.29 (3H, t). washed with Na2S2O3 solution, water and brine dried (MgSO4) filtered concentrated under reduced pressure The concentrate was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To ethyl 6-chloro-2-oxohexanoate (2.9 g, 15 mmol) in carbon tetrachloride (30 mL) was added bromine (0.85 mL, 16.5 mmol) and stirred at rt for 1 hour. The reaction mixture was diluted with EtOAc, washed with Na2S2O3 solution, water, brine, dried over MgSO4, filtered, and concentrated under reduced pressure. The crude material was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes to provide the desired product ethyl 3-bromo-6-chloro-2-oxohexanoate (2A) in 95% yield. 1H NMR (300 MHz, DMSO-d6) δ ppm 5.25 (1H, dd), 4.29 (2H, q), 3.71 (2H, t), 2.16 (1H, m), 1.91 (1H, m), 1.29 (3H, t). washed with Na2S2O3 solution, water, brine dried over MgSO4 filtered concentrated under reduced pressure The crude material was purified by column chromatography on silica gel eluting with a gradient of 0 to 10% EtOAc in hexanes