4-Methylmorpholine → tert-Butyl (2R)-2-{[(2-bromophenyl)amino]carbonyl}pyrrolidine-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a 500 mL flask, N-Boc-D-Proline (300 mg, 1.39 mmol) was dissolved in dichloromethane (35 mL) and cooled to 0° C. under nitrogen. N-Methylmorpholine (153 μL, 1.39 mmol) was added followed by dropwise addition of iso-butyl chloroformate (180 μL, 1.39 mmol) and the reaction mixture stirred at 0° C. for 1 h. 2-Bromoaniline (1.31 mL, 1.39 mmol) was dissolved in dichloromethane (5 mL) then added quickly to the activated acid at 0° C. The mixture was stirred overnight from 0° C. to room temperature. The reaction mixture was diluted with dichloromethane, washed with water, dried over Na2SO4 and concentrated under reduced pressure. The crude mixture was purified on column chromatography (eluent: Pentane/EtOAc, 50/50 to 0/100 then EtOAc/MeOH 80/20) to give the product (394 mg, 77%) as a yellow oil. This product was used in the next step without further purification.

Herkunft & Nachweise