Boc-L-beta-Homoproline

88790-37-8

56502-01-3

General procedure for the synthesis of (S)-2-(2-pyrrolidinyl)acetic acid from methyl (S)-2-(2-pyrrolidinyl)acetate: tert-butyl (2S)-2-(2-methoxy-2-oxoethyl)-1-pyrrolidinecarboxylate (8.35 g, 34.3 mmol) was dissolved in 150 mL of methanol. 50 mL of 1 M aqueous sodium hydroxide solution was added and the reaction mixture was stirred at room temperature overnight. Upon completion of the reaction, the solution was concentrated under reduced pressure to about 100 mL. The concentrated solution was added to 300 mL of water and extracted twice with ether (2 x 100 mL). The aqueous phase was acidified to pH 2 with 12N hydrochloric acid and extracted with ether twice more (2 x 100 mL). The aqueous layer was saturated with saturated sodium chloride solution and then extracted with ether a third time (100 mL). All organic layers were combined, washed sequentially with water and saturated sodium chloride solution, and then dried with anhydrous magnesium sulfate. The desiccant was removed by filtration and the filtrate was concentrated under reduced pressure to afford the title compound (S)-2-(1-tert-butoxycarbonyl-2-pyrrolidinyl)acetic acid as a white solid (7.28 g, 31.7 mmol, 92.6% yield). peaks, 4H), 1.48 (single peak, 9H) ppm.