Boron trifluoride etherate → HCID 131736871, compound

Participants

Reaction Steps

To a stirred solution of 1,2,3,4-tetra-O-acetyl-L-fucopyranose (200 g, 601.86 mmol) in AcCN (100 mL) and benzyl (2-hydroxyethyl)carbamate (140.96 g, 722.08 mmol) at 0° C. was added BF3.Et2O (427.7 g, 3.01 mol) dropwise over 2 hr. After stirring at rt for 16 hr, the reaction mixture was cooled to 0° C. and followed by the addition of Et3N (130 mL). The resulting mixture was concentrated and the residual was dissolved in CH2Cl2 (2.0 L), which was subsequently washed with sat. NaHCO3 (2×500 mL), water (2×500 mL) and brine (500 mL). The organic phase was separated, dried over Na2SO4, and concentrated. The residue was purified by flash chromatography on silica gel, eluting with EtOAc/petroleum ether (1:3) to give the title compound. 1H NMR (CDCl3) δ 7.33-7.37(5H, m), 5.12-5.32(5H, m), 4.99-5.04(1H, m), 4.42-4.45 (1H, d), 3.87-3.94 (1H, m), 3.78-3.84 (1H, m), 3.66-3.70(1H, m), 3.42-3.44 (2H, m), 2.19 (3H, s), 2.05-2.12(6H, m), 1.25-1.30 (3H, d).

Provenance & Evidence