tert-Butyl piperazine-1-carboxylate → 4-{2-[5-(2-Cyano-4-fluorophenoxy)-indazol-1-yl]-ethyl}-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of 5-fluoro-2-[1-(2-oxo-ethyl)-1H-indazol-5-yloxy]-benzonitrile (0.307 g, 1.04 mmol) and triacetoxyborohydride (0.66 g, 3.1 mmol) in dichloroethane (10 mL) was added piperazine-1-carboxylic acid tert-butyl ester (0.65 g, 3.49 mmol). The mixture was stirred at room temperature for 2 hours. The reaction mixture was quenched with MeOH (2 mL) and diluted with ethyl acetate (100 mL). The solution was washed with aqueous NaHCO3, brine, dried over MgSO4, and concentrated under reduced pressure. The residue was chromatographed eluting with ethyl acetate/hexanes (2:3, with 1% triethylamine) to afford 0.29 g of product (60% yield).

Provenance & Evidence