反应详情

温度

40 °C

A suspension of 6.5 g (12.3.10-3 mol) of 2,3,4-tri-O-acetyl-5-thio-α-D-xylopyranosyl bromide, 6 g (50.4.10-3 mol) of 4-hydroxybenzonitrile, 6.9 g (50.5.10-3 mol) of zinc chloride and 4.4 g (25.1.10-3 mol) of silver imidazolate in 200 ml of anhydrous methylene chloride is stirred at 40° C., under an inert atmosphere, in the absence of light and in the presence of a molecular sieve (400 pm). After 7 h at this temperature, 6.9 g (50.5.10-3 mol) of zinc chloride, 4.4 g (25.1.10-3 mol) of silver imidazolate and 6.5 g (18.3.10-3 mol) of 2,3,4-tri-O-acetyl-5-thio-α-D-xylopyranosyl bromide are added. The reaction medium is left overnight under these conditions and 6.5 g (12.3.10-3 mol) of 2,3,4-tri-O-acetyl-5-thio-α-D-xylopyranosyl bromide are then added. After 24 h, the reaction mixture is filtered on Celite® , washed with a 1N aqueous solution of hydrochloric acid and then water and dried over magnesium sulfate. After evaporation under reduced pressure, the residue is purified by chromatography on silica gel using a hexane/ethyl acetate mixture (3/1 v/v) as the eluent. 8.1 g (yield:41%) of the expected product are obtained by crystallization from ethanol.

1. additionare then added
2. filtrationthe reaction mixture is filtered on Celite®
3. washwashed with a 1N aqueous solution of hydrochloric acid
4. dry with materialwater and dried over magnesium sulfate
5. customAfter evaporation under reduced pressure
6. customthe residue is purified by chromatography on silica gel using a hexane/ethyl acetate mixture (3/1 v/v) as the eluent