2,2-Dimethyl-3-acetyloxypropionyl chloride → (3S)-1-Cbz-3-[cyclohexyl(acetyloxypivaloyl)amino]pyrrolidine

Participants

Reaction Conditions

Reaction Steps

To the mixture of (3S)-1-Cbz-3-(cyclohexylamino)pyrrolidine (3.0 g, 10 mmol), TEA (15 mL), and DMAP (1.25 g, 10 mmol) in THF (15 mL) was added 2,2-dimethyl-3-acetyloxypropionyl chloride (3.58 g, 20 mmol) prepared in Step A. After the reaction mixture was refluxed for 48 h (90-110° C.), the solvent was removed, and the residue was diluted with an aqueous NaHCO3 solution was added to the residue. The organic material was extracted with EtOAc, and the extracts were washed by 1N HCl, dried over MgSO4, and concentrated in vacuo. The crude product was purified by column chomatography (EtOAc/Hex=1/2) to give the title compound (2.80 g, 62.9%).

Provenance & Evidence