1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → 3-(5-amino-4-benzoyl-pyrazol-1-yl)-N-cyclopropyl-4-methylbenzamide

Participants

Reaction Steps

To a stirred solution of acid 4 (46 g, 0.143 mol, 1.0 equiv) in DMF (1.9 L) was added EDCI (57.5 g, 0.299 mol, 2.09 equiv), HOBt (41.4 g, 0.306, 2.14 equiv) and diisopropylethylamine (76.6 g, 0.59 mol, 4.15 equiv) and the solution was stirred for 20 minutes at room temperature. Then it was cooled to 15-20° C. and cyclopropylamine (20.6 g, 0.36 mol, 2.51 equiv) was added and stirred at room temperature. The reaction was monitored by TLC. After 14 hours, since the reaction was not complete and additional cyclopropylamine (9.36 g, 0.16 mol, 1.14 equiv) was added and stirring was continued for two hours. DMF was removed under reduced pressure at 50-55° C. To the residue EtOAc (1 L) and water (500 ml) were added and the mixture was stirred for 10 minutes. The mixture was extracted and the organic layer was collected. The aqueous layer was extracted with EtOAc (2×250 ml). The combined organic layer was washed with sodium bicarbonate (2×500 ml) and brine (2×500 ml), dried over anhydrous sodium sulfate and concentrated. To the residue EtOAc/dichloromethane/hexane (50 ml/50 ml/50 ml) was added, the mixtue was stirred for 10 minutes, and filtered to provide the product (34.1 g, 65.7%) as an off white crystalline solid. HPLC (Waters X-Terra 5 micron C18 column 4.6 mm×250 mm, 1.0 mL/min, mobile phase: 0.1% TEA in H2O/acetonitrile 50/50, 30 min elution) tR 5.53 min, 99.3% purity; MS m/z 360 [M]+; 1H NMR (DMSO-d6, 400 MHz) is consistent with Example 4.

Provenance & Evidence