Sodium Hydroxide → (2S,4S)-1-(Tert-butoxycarbonyl)-4-(2-naphthyloxy)-2-pyrrolidinecarboxylic acid

Participants

Reaction Steps

To a stirred solution of methyl (2S, 4S)-1-tert-butoxycarbonyl-4-(2-naphthyloxy)-2-pyrrolidinyl carboxylate (5.37 g) in THF (116 ml) was added 0.25 N NaOH (116 ml, 29.0 mmol) at room temperature. The resulting mixture was stirred over night. After removal of the solvent, the mixture was acidified by the addition of 1 N HCl and extracted with CHCl3. The combined extracts were washed with brine, dried over Na2SO4 and evaporated. The residue was recrystallized with n-hexane-CHCl3, to give (2S, 4S)-1-tert-butoxycarbonyl-4-(2-naphthyloxy)-2-pyrrolidinylcarboxylic acid [4.44 g, 85%(2 steps)] as a white powder. 1H-NMR (DMSO-d6) δ 1.37 and 1.41 (s, 9H, amide isomers), 2.26 (d, J=13.9 Hz, 1H), 2.65 (m, 1H), 3.47 (d, J=11.5 Hz, 1H), 3.81 (m, 1H), 4.30 (m, 1H), 5.14 (m, 1H), 7.02–7.86 (m, 7H).

Provenance & Evidence