Reaktion #531864

Reaktionsgleichung

1,2,3,4,6-Penta-O-acetyl-α-D-glucopyranose

Trimethylsilyl azide

tin (IV) chloride

→

2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl azide

Ausbeute 82.0%

Lösungsmittel

CH2Cl2

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   Waschenwashed twice with saturated NaHCO3 (20 mL) and with brine (20 mL)
2. 2
   SonstigeThe organic phase was dried
3. 3
   Filtrationfiltered
4. 4
   Einengenconcentrated

Vorschrift

1,2,3,4,6-Penta-O-acetyl-α-D-glucopyranose (5.00 g, 12.8 mmol) was dissolved in 10-15 mL dry CH2Cl2 under an inert atmosphere. Trimethylsilyl azide (4.24 mL, 32.1 mmol) and tin (IV) chloride (0.75 mL, 6.41 mmol) were added, and the reaction was stirred for 18 hours at room temperature. The reaction mixture was diluted with CH2Cl2 (30 mL) and washed twice with saturated NaHCO3 (20 mL) and with brine (20 mL). The organic phase was dried, filtered and concentrated to leave 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl azide as a white solid (3.92 g, 82%). 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl azide (0.30 g, 80 mmol) was then dissolved in dry THF (15 mL), and Pd/C was added (˜5%) to this solution. The mixture was stirred under H2 overnight. TLC revealed the reduction was completed (Rfazide=0.80, Rfamine=0.10). In a separate flask, compound 23 (0.17 g, 0.30 mmol) and 0.5 M HBTU in DMF (1.20 mL, 0.60 mmol) were combined, followed by the addition of DMF (˜2 mL) and DIEA (104 μL, 0.60 mmol). This solution was then added to the reaction flask, and the reaction mixture was stirred under N2 overnight. The resulting suspension was filtered through celite which was washed well with ethyl acetate (˜100 mL), and the filtrate was washed with 5 M HCl (50 mL), saturated NaHCO3 (2×50 mL), and brine (1×50 mL). The organic solution was dried over magnesium sulfate, filtered, and concentrated. The residue was purified using a silica gel column chromatography with 10% MeOH/DCM to yield V (0.16 g, 59.33). 1H NMR δ (CDCl3) 0.78 (3H, t, J=7 Hz), 1.16-1.23 (32H, brm), 1.35 (2H, m) 1.52 (2H, m) 1.57 (6H, brs), 1.86 (6H, brs), 1.91-2.00 (15H, m), 2.14 (2H, m), 2.99 (2H, t, J=7 Hz), 3.75 (2H, m), 3.95-4.07 (3H, m), 4.15-4.29 (4H, m), 4.43-4.38 (1H, m) 4.80 (1H, dd, J=5, 11 Hz), 4.84-4.89 (2H, m), 4.95-5.02 (3H, m), 5.12-5.24 (3H, m), 5.35 (1H, d, J=3 Hz), 5.47 (1H, t, J=9.8 Hz), 6.28 (1H, dd, J=7.6, 19 Hz), 6.60 (1H, d, J=9.3 Hz), 7.18 (1H, d, J=9.1 Hz), 7.34 (1H, d, J=9.1 Hz). LC-MS (ESI) m/z calcd for C47H78N4O12 [M+H]+ 891.56. found [M+H]+ 891.69.

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