反应详情

Digoxin (0.4985 g, 0.64 mmole) was dissolved in 10 ml of chloroform/methanol (3/1.5) and placed into a 100 ml two-necked flask. Sodium periodate (0.3102 g, 1.4 mmoles) was dissolved in 4 ml distilled water and placed into a pressure equalized addition funnel. The periodate solution was slowly added to the flask while stirring and under nitrogen. A white precipitate was immediately formed and the reaction was complete within 15 minutes after addition of the periodate. Reaction progress was monitored by TLC (E. M. Merck, pre-coated TLC sheets, silica gel 60 F254 0.2 mm thickness) in chloroform/methanol 10/1 by volume Rf 0.16=dialdehyde, one homogeneous spot; Rf 0.07=Digoxin. Both spots became dark brownish when the TLC plate was sprayed with methanol/concentrated sulfuric acid (9/1 by volume) and placed in an oven at 100° C. The reaction mixture was evaporated on a rotatory evaporator and brought up in 30 ml of chloroform and 3 ml of water. The cloudy solution was extracted and the aqueous layer washed three times with 10 ml chloroform. The organic phases are combined (60 ml) and dried over magnesium sulfate. The organic solvents are evaporated to dryness. A light yellow brownish oily material was left. This material was used immediately in the next reaction.

1. customplaced into a 100 ml two-necked flask
2. distillationdistilled water
3. additionaddition funnel
4. additionThe periodate solution was slowly added to the flask
5. customA white precipitate was immediately formed
6. customReaction progress
7. customplaced in an oven at 100° C
8. customThe reaction mixture was evaporated on a rotatory evaporator
9. extractionThe cloudy solution was extracted
10. washthe aqueous layer washed three times with 10 ml chloroform
11. dry with materialdried over magnesium sulfate
12. customThe organic solvents are evaporated to dryness
13. waitA light yellow brownish oily material was left
14. customThis material was used immediately in the next reaction