amino 4-chlorobenzoate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred, ice/water cooled mixture of 1H-pyrrole-2-carboxylic acid methyl ester (425 mg, 3.40 mmol) in NMP (10 mL) was added a solution of potassium tert-pentoxide in toluene (2.30 mL, 3.90 mmol, 25 wt % solution); then the solid of O-4-chlorobenzoyl hydroxyamine (670 mg, prepared according to the literature: Parlanti, L Discordia, R. P.; Hynes, J. Jr.; Miller, M. M.; O'Grady, H. R.; Shi, Z. Org. Lett. 2007, 9(19) 3821-3824) was added in one portion; the cold bath was removed after addition completed, and the slurry was stirred at rt for 30 min. Subsequently, the reaction was quenched by addition of saturate sodium bicarbonate solution, then extracted with EtOAc, washed with brine; organic layers was dried over anhydrous sodium sulfate, filtered, concentrated and the residue was column purified to give the desired product (309 mg). 1H NMR (CDCl3, δ in ppm): 6.94 (t, 1H, J=2.3 Hz), 6.81 (dd, 1H, J=2.0 Hz, 4.0 Hz), 6.00 (dd, J=2.7 Hz, 4.3 Hz), 5.53 (br, s, 2H), 3.82 (s, 3H). 2007, 9(19) 3821-3824) was added in one portion the cold bath was removed after addition Subsequently, the reaction was quenched by addition of saturate sodium bicarbonate solution extracted with EtOAc washed with brine organic layers was dried over anhydrous sodium sulfate filtered concentrated purified