反应详情

A solution of ManNAc (5.0 g, 2.6 mmol), and Ac2O (10 mL) in pyridine (20 mL) was stirred for 10 hours at room temperature, and the mixture was concentrated, followed by coevaporation with toluene. A solution of the residue, allyl alcohol (2.63 g, 45.2 mmol; 3.1 mL), BF3 ·OEt2 (1.60 g, 11.3 mmol; 1.39 mL) in CH3NO2 (150 mL) was gently refluxed for 2.5 hours. After cooling, the mixture was concentrated. The residue was chromatographed on silica gel, with toluene-EtOAc (1:2) to give allyl 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-α-D-mannopyranoside in 6.47 g (74 percent);

1. concentrationthe mixture was concentrated
2. temperatureAfter cooling
3. concentrationthe mixture was concentrated
4. customThe residue was chromatographed on silica gel, with toluene-EtOAc (1:2)