Reaction Steps
Acetyl chloride (4.5 mL, 63.3 mmol) was added dropwise to a solution of tert-butyldimethylsilyl 2-azido-3-O-benzyl-2-deoxy-β-D-glucopyranoside (25 g, 61 mmol) in 2,4,6-collidine (110 mL) under nitrogen at −40° C. After stirring at −40° C. overnight, water was added. The mixture was poured into EtOAc and extracted with 1 N HCl, brine and saturated NaHCO3. The organic phase was dried over Na2SO4, filtered and the solvents were removed in vacuo to afford 6 (26.5 g, 58.7 mmol, 96%) as a colorless solid. [α]24D: −27.1 (c 1.00, CH2Cl2); IR (thin film) 3482, 2110, 1743, 1255 cm−1; 1H-NMR (300 MHz, CDCl3) δ 7.43-7.30 (m, 5H), 4.96 (d, J=11.4 Hz, 1H), 4.73 (d, J=11.4 Hz, 1H), 4.55 (d, J=7.6 Hz, 1H), 4.34-4.27 (m, 2H), 3.50-3.38 (m, 2H), 3.33 (dd, J=7.6, 9.9 Hz, 1H), 3.21 (dd, J=8.3, 9.9 Hz, 1H), 2.59-2.46 (br s, 1H), 2.09 (s, 3H), 0.96 (s, 9H), 0.18 (s, 6H); 13C-NMR (75 MHz, CDCl3) δ 171.5, 138.1, 128.8, 128.31, 128.28, 97.4, 82.2, 75.3, 73.8, 70.3, 68.3, 63.5, 25.8, 21.1, 18.3, −4.1, −5.0; FAB MS (C21H33N3O6Si) m/z (M+) calcd 451.2138, obsd 451.2135.
