Hydrochloric Acid → (S)-tert-Butyl 2-(((S)-1-amino-1-oxo-3-phenylpropan-2-yl)carbamoyl)pyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of Boc-Pro-OH (4.304 g, 20 mmoles) in ethyl acetate (200 mL) at -15° C., N-methylmorpholine (2.2 mL, 20 mmoles) and isobutyl chloroformate (2.6 mL, 20 mmoles) were added. After an activation time of 10 minutes at -15° C., a solution of HCl.Phe-NH2 (4.014 g, 20 mmoles) and N-methylmorpholine (2.2 mL, 20 mmoles) in dimethylacetamide (20 mL) was added. The reaction mixture was stirred at -15° C. for 30 minutes and allowed to warm to room temperature. After stirring for 2 hours at room temperature, the reaction mixture was quenched with 10% potassium carbonate solution (30 mL). The two clear layers were transferred to a separatory funnel, and the organic layer was washed successively with 10% potassium carbonate solution (2×30 mL), saturated sodium chloride solution (1×30 mL), IN HCl (2×30 mL) and saturated sodium chloride solution (2× 30 mL). After drying over anhydrous sodium sulfate, the organic solution was filtered and concentrated on a rotary evaporator under house vacuum. The product was precipitated with hexane, filtered and dried.

Provenance & Evidence