1,2-Dichloroethane → 4-{N'-[4-(2-ethyl-5,7-dimethyl-pyrazolo[1,5-a]pyrimidin-3-ylmethyl)-benzoyl]-hydrazinocarbonyl}-piperidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A 500 ml four-necked flask equipped with an overhead stirrer and a thermocouple was charged with acid 27 (10.0 g, 32.3 mmol, 1.0 eq), 120 ml of DMF and 2,4,6 trimethylpyridine (11.75 g, 96.9 mmol) under nitrogen purge. After stirring the reaction mixture for 30 min at 23° C., 4-hydrazinocarbonyl-piperidine-1-carboxylic acid tert-butyl ester (9.4 g, 38.7 mmol, 1.2 eq), EDC (12.3 g, 64.3 mmol), HOBT (1.48 g, 9.6 mmol) were added. The reaction mixture was stirred for 12 h at 23° C. After completion of the reaction, it was diluted with i-PrOAc/heptane (100 mL, 1:1) and followed by water (250 ml) at 23° C. The suspension was stirred for 1 h at 23° C. The solid was collected by filtration and washed with 50 ml of water. The wet product was dried at 40° C. for 12 h to obtain a white solid.

Provenance & Evidence