Diisopropylethylamine → Biphenyl-2-ylcarbamic Acid 1-[2-(4-Aminomethylphenylcarbamoyl)ethyl]piperidin-4-yl Ester

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 4-(N-tert-butoxycarbonylaminomethyl)aniline (756 mg, 3.4 mmol), 3-[4-(biphenyl-2-ylcarbamoyloxy)piperidin-1-yl]propionic acid (1.5 g, 4.08 mmol; prepared as described in Preparation 3) and HATU (1.55 g, 4.08 mmol) in DMF (6.8 mL), was added DIPEA (770 μL, 4.42 mmol). The reaction mixture was stirred at 50° C. overnight, and then the solvent was removed under reduced pressure. The resulting residue was dissolved in DCM (20 mL) and washed with saturated aqueous sodium bicarbonate solution (10 mL). The organic phase was then dried (magnesium sulfate) and the solvent was removed under reduced pressure. The crude product was purified by flash chromatography (5-10% MeOH/DCM) to give a solid, which was dissolved in TFA/DCM (25%, 30 mL) and stirred at room temperature for 2 hours. The solvent was then removed under reduced pressure and the crude residue was dissolved in DCM (30 mL) and washed with 1N NaOH (15 mL). The organic phase was separated, dried (magnesium sulfate), filtered and the solvent was removed under reduced pressure to give 1.5 g of the title intermediate (94% yield over 2 steps).

Provenance & Evidence