1-Hydroxybenzotriazole → tert-Butyl cis(+/-)-4-{[(4-chloro-5-ethyl-1H-imidazol-2-yl)carbonyl]amino}-3-isobutoxypiperidine-1-carboxylate

Participants

Reaction Steps

The same operation as in Example (106d) was performed using tert-butyl cis(±)-4-amino-3-isobutoxypiperidine-1-carboxylate obtained in Example (117d) (1.26 g, 4.6 mmol), 4-chloro-5-ethyl-1H-imidazole-2-carboxylic acid (85% content, 1.02 g, 5 mmol), WSC hydrochloride (2.88 g, 15 mmol), HOBt (1.01 g, 7.5 mmol), DMA (15 mL) and dichloromethane (15 mL). The resulting residue was purified by silica gel column chromatography (elution solvent: ethyl acetate/hexane=1/4, 2/3, 3/2, 4/1) to obtain 1.71 g of the title compound as a colorless solid (87%).

Provenance & Evidence