Trifluoroacetic acid → (R)-1-[3-[[3-[(R)-2-Carboxy-pyrrolidin-1-yl]-3-oxo-propyl]-(4-trifluoromethyl-benzyl)-amino]-propionyl]-pyrrolidine-2-carboxylic acid trifluoroacetate

Participants

Reaction Steps

To a stirred solution of 200 mg (0.32 mmol) (R)-1-[3-[[3-[(R)-2-tertbutoxycarbonyl-pyrrolidin-1-yl]-3-oxo-propyl]-(4-trifluoromethylbenzyl)-amino]-propionyl]-pyrrolidine-2-carboxylic acid tert-butyl ester in 5 ml dichloromethane at 0° C. was added dropwise 1.0 ml trifluoroacetic acid and stirring continued for 16 h at room temperature. Concentration in vacuo and azeotroping three times with chloroform on a rotary evaporator afforded, after trituration in ether, 150 mg (75%) of the title compound as a yellow crystalline solid. MS m/e (%): 536 (M+Na+, 20), 514 (M+H+, 100).

Provenance & Evidence