Sodium Carbonate → HCID 86589109, compound

Participants

Reaction Steps

To a stirred solution of (2S,3S)-4-fluorothreonine 101 (0.100 g, 0.82 mmol) in THF/H2O (1:1, 5 ml) adjusted to pH 9 using sodium carbonate was added N-carboxybenzyloxysuccinimide (0.308 g, 1.24 mmol). After stirring the solution for 18 hours at room temperature, the solvent was removed in vacuo to give a white residue. The residue was partitioned between ethyl acetate (5 ml) and water (10 ml). The organic layer was separated and aqueous layer further extracted with ethyl acetate (2×5 ml), this organic phase was discarded. The pH of the aqueous layer was adjusted to 3 using 1N HCl. The aqueous layer was extracted with ethyl acetate (4×10 ml), the combined organic layers were dried (MgSO4) and the solvent removed in vacuo to afford N-carboxybenzyloxy-(2S,3S)-4-fluorothreonine 102 as a pale yellow oil (110 mg, 70% yield); 1H (400 MHz, CDCl3) 8.20 (1H, bs, OH, exchange with CH3OD), 6.46, 6.45 and 6.07 (1H, 3×d, J 8.9), 5.10-4.85 (2H, m, CH2Ph), 4.65-4.25 (4H, H-2, H-3 and 4-CH2); 19F (376 MHz, CDCl3) −228.59 and −228.51 (2×dtJ 46,14 due to rotamers).

Provenance & Evidence