反应详情

A 1:2 mixture of the α and β anomers of methyl 3-O-benzyl-5-cyano-5-deoxy-2-O-trifluoromethanesulphonyl-D-xylofuranoside (21αβ) (2.51 g, 6.36 mmol) dissolved in cyclohexane (200 ml) at 40° C. was treated with borane-dimethyl sulphide complex (10M in THF, 955 μl, 9.55 mmol) then stirred at room temperature overnight. Methanol (1 ml) was added, and the solvents evaporated then replaced with a 1:1 mixture of methanol and pyridine (50 ml). This was stirred with potassium carbonate (5 g) at room temperature for 48 hours. The solvents were removed and the residue dissolved in dichloromethane (20 ml), filtered and concentrated by evaporation. Purification using flash chromatography produced methyl 3-O-benzyl-2,6-imino-2,5,6-trideoxy-D-lyxohexofuranoside (α:β 1:2) (1.52 g, 96%) as a partially separated mixture of colourless oils which rapidly turn brown on storage.

1. customthe solvents evaporated
2. additionthen replaced with a 1:1 mixture of methanol and pyridine (50 ml)
3. stirringThis was stirred with potassium carbonate (5 g) at room temperature for 48 hours
4. customThe solvents were removed
5. dissolutionthe residue dissolved in dichloromethane (20 ml)
6. filtrationfiltered
7. concentrationconcentrated by evaporation
8. customPurification