Chloroacetic Acid → HCID 86590377, compound

Participants

Reaction Steps

A solution of of the (2R,3R)-3-tert-butoxycarbonylamino-4-(3-fluoro-phenyl)-2-hydroxy-butyric acid methyl ester (8 g, 24.5 mmol, 1 eq), chloroacetic acid (5.79 g, 61.3 mmol, 2.5 eq), and PPh3 (16 g, 61.3 mmol, 2.5 eq) in benzene (340 mL) was cooled to 0 C followed by the addition of diethylazodicarboxylate (9.7 mL, 61.3 mmol, 2.5 eq) over a 20 min period. After the addition, the reaction mixture was stirred at ambient temperature for 2 h after which the reaction mixture was concentrated and the residue purified by column chromatography with 30% EtOAc/hexanes as eluant. Appropriate fractions were combined and concentrated to give a yellow solid which was shaken with heptane and filtered to remove the yellow DEAD residues. The product was thus obtained as a white solid (4.25 g, 43%) 1H NMR (CDCl3) 7.32 (m, 1H), 7.03–6.96 (m, 3H), 5.34 (d, J=3.5, 1H), 4.26 (s, 2H), 4.75–4.5 (series of m, 2H), 3.77 (s, 3H), 2.92 (bd, J=7, 2H), 1.43 (s, 9H).

Provenance & Evidence