Ethyl Acetate → 1-cyclopentyl N-[1-(tert-butoxycarbonyl)pyrrolidin-3-yl]-L-leucinate

Participants

Reaction Steps

To a solution of N-tert-butoxycarbonyl-3-pyrrolidinone (0.382 g, 4.76 mmol) in dichloroethane (20 mL) was added L-leucine cyclopentyl ester tosylate (1.96 g, 5.3 mmol) and sodium triacetoxyborohydride (2.65 g, 12.5 mmol). The mixture was stirred at room temperature for 3 hours, then poured into ethyl acetate (150 mL) and quenched with saturated ammonium chloride solution (50 mL) and washed with saturated sodium hydrogen carbonate solution (3 times 30 mL). The organic extracts were dried (MgSO4), concentrated and purified by flash column chromatography (7:3 ethyl acetate:heptane) to yield the desired product. LC/MS: m/z 369.25 [M+H]+

Provenance & Evidence