반응 #11385

반응 방정식

2-acetamido-4-fluoro-2,4-dideoxy-D-glucopyranose

acetic anhydride

→

2-acetamido-1,3,6-tri-O-acetyl-2,4-dideoxy-4-fluoro-D-glucopyranose

용매

pyridine

반응 조건

후처리

1. 1
   기타close spots
2. 2
   workup.STIRRINGStirring
3. 3
   workup.WAITcontinued for another 15 hours
4. 4
   기타Solvent was then removed by evaporation in vacuo
5. 5
   기타then dried in vacuo
6. 6
   workup.ADDITIONpoured in CH2Cl2/acetone (8:1)
7. 7
   세척The column was eluted with 500 ml of CH2Cl2/acetone (8:1)
8. 8
   세척eluted immediately
9. 9
   기타with virtually no separation
10. 10
    기타The CH2Cl2/CH3OH flush
11. 11
    기타produced a trailing spot
12. 12
    기타All were evaporated
13. 13
    기타dried in vacuo

실험 절차

A solution of 2-acetamido-4-fluoro-2,4-dideoxy-D-glucopyranose (1.35 g, 6.048 mmol) in a mixture of pyridine (50 ml) and acetic anhydride (25 ml, 27 g, 264 mmol) was stirred at room temperature for 24 hours at which time no starting material but two close spots appeared by TLC. Stirring continued for another 15 hours. Solvent was then removed by evaporation in vacuo; the residue was now co-evaporated with toluene (4×50 ml) then dried in vacuo. This material was now adsorbed on 5 g of silica gel then placed on a silica gel column (45 g, 20×360 mm) poured in CH2Cl2/acetone (8:1). The column was eluted with 500 ml of CH2Cl2/acetone (8:1) followed by 500 ml of CH2Cl2/CH3OH (7:3). The product and trailing spots eluted immediately, with virtually no separation. The CH2Cl2/CH3OH flush produced a trailing spot. All were evaporated and dried in vacuo.

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