(2S,4R)-4-hydroxy-2-methyl-pyrrolidine-1-carboxylic acid tert-butyl ester

213699-41-3

114676-61-8

Tert-butyl (2S,4R)-4-((tert-butyldimethylsilyl)oxy)-2-methylpyrrolidine-1-carboxylate (2.2 g, 6.98 mmol) was dissolved in tetrahydrofuran (30 mL), followed by addition of tetrabutylammonium fluoride (3.65 g, 14.0 mmol). The reaction mixture was stirred at room temperature overnight. After completion of the reaction, the mixture was poured into water (60 mL) and extracted with ethyl acetate (60 mL x 2). The organic phases were combined, washed with saturated sodium chloride solution (60 mL x 2) and dried over anhydrous sodium sulfate. The solvent was removed by concentration under reduced pressure and the resulting crude product was purified by column chromatography (petroleum ether: ethyl acetate = 2:1) to give 1.47 g of a yellow oily product, i.e. tert-butyl (2S,4R)-4-hydroxy-2-methylpyrrolidine-1-carboxylate in 99% yield.