Acetyl chloride → 4-[(Acetylphenylamino)-methyl]-1H-pyrrole-2-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

4-Phenylaminomethyl-1H-pyrrole-2-carboxylic acid ethyl ester (183) (0.1523 g, 0.623 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 (1.6 mL, 0.4 M) and then the flask was cooled to 0° C. N,N-diisopropyl ethyl amine (0.1194 mL, 0.686 mmol) was added, then acetyl chloride (0.0488 mL, 0.686 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 (35 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 sufficiently pure by HPLC and NMR analysis that it was used in the next step without further purification (0.1625 g, 91%, white crystalline solid). 1H (CD3OD, 400 MHz): δ 11.22 (1H, broad s), 7.43-7.31 (3H, m), 7.08 (2H, dd, J=7.0, 1.5 Hz), 6.75 (1H, d, J=1.5 Hz), 6.68 (1H, d, J=1.5 Hz), 4.70 (2H, s), 4.24 (2H, q, J=7.0 Hz), 1.81 (3H, s), 1.31 (3H, t, J=7.0 Hz) ppm. 13C (CD3OD, 100 MHz): δ 172.47, 162.64, 143.86, 130.68, 129.34, 129.27, 124.50, 124.33, 122.19, 116.72, 61.16, 46.60, 22.64, 14.75 ppm. DEPT (CD3OD, 100 MHz): CH3 carbons: 22.64, 14.75; CH2 carbons: 61.16, 46.60; CH carbons: 130.68, 129.34, 129.27, 124.33, 116.72 ppm. HPLC: 8.738 min.

Provenance & Evidence