Trimethylsilyl triflate → 3-(2,3,4-tri-O-acetyl-alpha-L-fucopyranosyl)-1-propene

Participants

Reaction Conditions

Reaction Steps

To a solution of 1,2,3,4-tetra-O-acetyl-α-L-fucopyranose (12 g, 36.1 mmol) and allyltrimethyl silane (11.48 mL, 72.2 mmol) in AcCN (60 mL) at 0° C. was added TMS-OTf (3.52 mL, 19.50 mmol). The reaction mixture was stirred at 0° C. for 18 hr and then at rt for 6 hr. The resulting red solution was diluted with CH2Cl2 (250 mL) and sat'd NaHCO3 (150 mL) was added carefully. The aqueous layer was separated and extracted with CH2Cl2 (2×50 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated. The residue was purified by flash chromatography on silica gel (220 g), eluting with 15% EtOAc in hexanes to give the title compound. 1H NMR (CDCl3, 400 MHz) δ 1.16 (d, J=6.4, 3H), 2.04 (s, 3H), 2.08 (s, 3H), 2.18 (s, 3H), 2.34 (m, 1H), 2.57 (m, 1H), 4.00 (m, 1H), 4.29 (dt, J=10.4, 7.3, 1H), 5.13 (m, 2H), 5.23 (dd, J=10.0, 3.4, 1H), 5.30 (dd, J=3.4, 1.9, 1H), 5.35 (dd, J=10.0, 5.6, 1H), 5.77 (m, 1H).

Provenance & Evidence