反应详情

温度

0 °C

4-[(4-chlorophenylamino)-methyl]-1H-pyrrole-2-carboxylic acid ethyl ester (187) (0.2868 g, 1.03 mmol) was weighed out into a 10 mL flask. A stir bar and septum were added, and the flask was purged with nitrogen. The amine was dissolved in methylene chloride (2.6 mL, 0.4 M) and then the flask was cooled to 0° C. N,N-diisopropyl ethyl amine (0.1971 mL, 1.13 mmol) was added, then acetyl chloride (0.0805 mL, 1.13 mmol) was added slowly by syringe to the stirring 0° C. solution. The reaction was then allowed to warm to room temperature. When the reaction was judged complete by HPLC (90 min) the reaction was diluted with methylene chloride and quenched with water. The organic phase was removed, washed with brine, dried with Na2SO4, filtered and concentrated en vacuo. The crude product was purified by silica gel chromatography (Combiflash column, 2:1 Hexanes:Ethyl acetate) to obtain pure 4-[(acetyl-(4-chlorophenyl)-amino)-methyl]-1H-pyrrole-2-carboxylic acid ethyl ester (189, 0.2701 g, 82%) as a sticky white solid. 1H (CD3OD, 400 MHz): δ 11.25 (1H, broad s), 7.35 (2H, d, J=8.4 Hz), 7.05 (2H, d, J=8.4 Hz), 6.76 (1H, s), 6.69 (1H, s), 4.68 (2H, s), 4.22 (2H, q, J=7.1 Hz), 1.81 (3H, s), 1.29 (3H, t, J=7.1 Hz) ppm. 13C (CD3OD, 100 MHz): δ 172.17, 162.50, 142.39, 134.87, 130.94, 130.70, 124.46 & 124.30, 123.94, 121.91 & 121.88, 116.64, 61.13, 46.43, 22.70, 14.75 ppm. DEPT (CD3OD, 100 MHz): CH3 carbons: 22.70, 14.75; CH2 carbons: 61.13, 46.43; CH carbons: 130.94, 130.70, 124.46 & 124.30, 116.64 ppm. HPLC: 9.247 min.

1. additionA stir bar and septum were added
2. customthe flask was purged with nitrogen
3. dissolutionThe amine was dissolved in methylene chloride (2.6 mL, 0.4 M)
4. temperatureto warm to room temperature
5. customwas judged complete by HPLC (90 min)
6. customquenched with water
7. customThe organic phase was removed
8. washwashed with brine
9. dry with materialdried with Na2SO4
10. filtrationfiltered
11. concentrationconcentrated en vacuo
12. customThe crude product was purified by silica gel chromatography (Combiflash column, 2:1 Hexanes:Ethyl acetate)