Methyl iodide → (2R,4R)-4-Hydroxy-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester

Participants

Reaction Conditions

Reaction Steps

Iodomethane (4.17 ml) was added to (2R,4R)-1-tert-butoxycarbonyl-4-hydroxy-pyrrolidine-2-carboxylic acid (15.00 g) in DMF (100 ml) at 0° C. Caesium carbonate (25.4 g) was added in one portion and the resulting mixture stirred at 20° C. for 16 hours. The reaction mixture was diluted with water (150 ml) and extracted with dichloromethane (2×150 ml). The combined organics were washed with brine (100 ml), dried over Magnesium sulphate, filtered and evaporated to dryness to give O1-tert-butyl O2-methyl (2R,4R)-4-hydroxypyrrolidine-1,2-dicarboxylate (13.83 g) as a yellow oil. 1 NMR Spectrum: (DMSOd6) 1.32 (9H, s); 1.77-1.85 (1H, m); 2.24-2.38 (1H, m); 3.07-3.15 (1H, m); 3.47 (1H, q); 3.63 (3H, t); 4.16-4.23 (2H, m); 4.92-4.98 (1H, m).

Provenance & Evidence