反应详情

Glycolaldehyde (0.100 mmol, in dimeric form) was dissolved in 1.0 mL anhydrous hydrazine (Pierce or Aldrich Chemical Company) in a Pierce reacti-vial, and capped under nitrogen with a cap having a Pierce Tuf-bond teflon-silicone seal. The sample, after sitting at room temperature for 16 hours, was converted to the hydrazone derivative of glycolaldehyde which was evaporated to a resin-like material in a Speed-Vac concentrator. The sample was quantitatively transferred in a 1.0 mL volume of water into a 20 mL test tube, and 100 mg of sodium borohydride was added, which reduced the molecule to 2-hydrazinoethanol. After 24 hours, the sample was placed in an ice-water bath and 0.200 mL of glacial acetic acid was added, dropwise, over about a 30 second interval. The sample was diluted with 1.0 mL water. To it was added 200 mg of sodium bicarbonate and the bicarbonate was permitted to dissolve, with occasional mixing. Then, 0.100 mL acetic anhydride was added, followed by gentle swirling to dissolve all of it. After 10 minutes, another 0.100 mL acetic anhydride was added, the solution gently swirled to dissolve it, and, after an additional 50 minutes, the sample was diluted with 5.0 mL water and loaded on a column containing 10-12 mL of well-washed Dowex AG1-X8, 100-200 mesh, H+ form, to remove sodium. The column was washed with five additional washes of 10 mL water. The total eluate was rotary evaporated to near dryness, and then rotary evaporated to dryness five times with 20 mL of 1% acetic acid in methanol, and three times with 20 mL methanol alone, to remove boric acid, thereby resulting in 2-(N,N'-diacetylhydrazino)-ethanol. This sample contained some additional N,N'-diacetylhydrazine. It was either directly O-peracetylated on the free hydroxyl group as described below, or it was chromatographically purified prior to O-acetylation by high-performance liquid chromatography on a Waters GlycoPak N column (7.8×300 mm), using isocratic acetonitrile/water, at 85/15, vol/vol, at 1.0 mL/min, monitoring at a wavelength of 200 nm, giving a single product peak at 17 minutes. For O-acetylation, 1.0 μmol of 2-(N,N'-diacetylhydrazino)-ethanol, either before or after liquid chromatographic purification was dried in a Pierce reacti-vial in a Speed-Vac rotary concentrator. The dried samples were taken up in 100 μL of dry pyridine (Pierce, silylation grade) and 50 μL acetic anhydride was added. The samples were kept under argon for 24 hours at room temperature, whereupon the solvent was removed under a flow of nitrogen. The samples were solubilized in about 0.5 mL chloroform, and again concentrated under a flow of nitrogen. These data show that the product is 2-hydrazinoethanol triacetate.

1. customcapped under nitrogen with a cap
2. customseal
3. customwas evaporated to a resin-like material in a Speed-Vac concentrator
4. customThe sample was quantitatively transferred in a 1.0 mL volume of water into a 20 mL test tube
5. addition100 mg of sodium borohydride was added
6. waitAfter 24 hours
7. customthe sample was placed in an ice-water bath
8. addition0.200 mL of glacial acetic acid was added
9. customover about a 30 second interval
10. additionThe sample was diluted with 1.0 mL water
11. additionTo it was added 200 mg of sodium bicarbonate
12. dissolutionto dissolve, with occasional mixing
13. additionThen, 0.100 mL acetic anhydride was added
14. dissolutionto dissolve all of it
15. waitAfter 10 minutes
16. additionanother 0.100 mL acetic anhydride was added
17. dissolutionto dissolve it
18. waitafter an additional 50 minutes
19. additionthe sample was diluted with 5.0 mL water
20. additioncontaining 10-12 mL of well-washed Dowex AG1-X8, 100-200 mesh, H+ form
21. customto remove sodium
22. washThe column was washed with five additional washes of 10 mL water
23. customThe total eluate was rotary evaporated
24. customrotary evaporated to dryness five times with 20 mL of 1% acetic acid in methanol, and three times with 20 mL methanol alone
25. customto remove boric acid
26. customresulting in 2-(N,N'-diacetylhydrazino)-ethanol
27. customwas chromatographically purified
28. customat 85/15, vol/vol, at 1.0 mL/min, monitoring at a wavelength of 200 nm, giving a single product peak at 17 minutes
29. customwas dried in a Pierce reacti-vial in a Speed-Vac rotary concentrator
30. addition50 μL acetic anhydride was added
31. waitThe samples were kept under argon for 24 hours at room temperature, whereupon the solvent
32. customwas removed under a flow of nitrogen
33. concentrationagain concentrated under a flow of nitrogen