反应详情

Palladium black is prepared from 13 g of palladium chloride in the manner described in Example 1. A solution of 30.0 g of diethyl phosphate and 2R,3S 3',4',5,7-tetrabenzyloxy-flavan-3-yl phosphate in 1.3 l of ethyl acetate are added. The hydrogenation is carried out for 3 hours and 3.9 l of hydrogen are consumed. The palladium is filtered off and washed twice with 200 ml of ethyl acetate. The combined solutions are evaporated to dryness. 750 ml of water are added to the residue and evaporated under reduced pressure to a volume of approximately 100 ml. This operation is repeated twice then the product is lyophilised. Diethyl phosphate and 2R,3S 3',4',5,7-tetrahydroxy-flavan-3-yl phosphate are obtained. Mp.: 121°-123°.

1. custom3.9 l of hydrogen are consumed
2. filtrationThe palladium is filtered off
3. washwashed twice with 200 ml of ethyl acetate
4. customThe combined solutions are evaporated to dryness
5. addition750 ml of water are added to the residue
6. customevaporated under reduced pressure to a volume of approximately 100 ml