(2S,3S)-3-(tert-Butyl-dimethyl-silanyloxy)-2-(4-cyano-naphthalen-1-ylcarbamoyl)-pyrrolidine-1-carboxylic acid tert-butyl ester → (2S,3S) 3-Hydroxy-pyrrolidine-2-carboxylic acid (4-cyano-naphthalen-1-yl)-amide

Participants

Reaction Steps

A solution of 30C (700 mg, 1.4 mmol) in dry CH2Cl2 (2.8 ml) and TFA (2.8 ml) was stirred at RT for 4 days. The reaction mixture was diluted with CH2Cl2 (35 ml), concentrated to a syrup and stripped with toluene (35 ml) and ether (2×20 ml). The residual syrup was dissolved in water (7.0 ml), basified with 1.0 N NaHCO3 (5.0 ml) to pH 8.0, extracted with CH2Cl2 (2×100 ml) and the combined organic extracts were dried (Na2SO4) and concentrated. Purification by automated flash chromatography (35 g silica gel column, EtOAc/hexane gradient) gave the title compound as an off-white solid (249 mg, 83.4%), m.p. 174–176° C. MS (ES): m/z 282 [M+1]+.

Provenance & Evidence