Methanol → (4R)-4-Hydroxy-L-proline methyl ester

Participants

Reaction Steps

Thionyl chloride (47 g, 393 mmol) was added dropwise at 0° C. to a stirred solution of (2S,4R)-4-hydroxy-pyrrolidine-2-carboxylic acid (40 g, 0.31 mol) in anhydrous methanol (200 mL). The reaction was allowed to proceed overnight, and concentrated to give the title intermediate (50 g). 1H NMR (400 MHz, CD3OD) δ (ppm) 4.56 (m, 2H), 3.85 (s, 3H), 3.41 (m, 1H), 3.28 (m, 1H), 2.40 (m, 1H), 2.22 (m, 1H).

Provenance & Evidence