Réaction #302915

Équation de réaction

diethyl azodicarboxylate

K2CO3

7

1-(3-O-Acetyl-2,5-dideoxy-5-iodo-β-D-threo-pentofuranosyl)-thymine

Ph3P

AcOH

→

8

Rendement 127.4%

1-(3-O-Acetyl-2,5-dideoxy-β-L-glycero-pent-4-enofuranosyl)-thymine

Rendement 127.4%

Solvants

MeOH

THF

Conditions de réaction

Traitement

1. 1
   Températurewas cooled to 0 under positive pressure of dry Ar
2. 2
   Autrethe mixture was partitioned between CH2Cl2 and sat. aqueous NaHCO3
3. 3
   SéchageThe organic layer was dried (Na2SO4)
4. 4
   Autreevaporated
5. 5
   AutreThe mixture was partitioned between CHCl3 and brine
6. 6
   SéchageThe organic layer was dried (Na2SO4)
7. 7
   Autreevaporated
8. 8
   Autrechromatographed on a silica gel column (hexane/EtOAc=4/1)

Mode opératoire

A mixture of 7 (1.08 g, 2.63 mmol), Ph3P (897 mg, 3.42 mmol) and AcOH (301 μL, 5.26 mmol) in THF (10 mL) was cooled to 0 under positive pressure of dry Ar. To this was added dropwise diethyl azodicarboxylate (2.3 M solution in toluene, 1.49 mL, 3.42 mol). After stirring for 30 min, the mixture was partitioned between CH2Cl2 and sat. aqueous NaHCO3. The organic layer was dried (Na2SO4) and evaporated. The residue was treated with K2CO3 (727 mg, 5.26 mmol) in MeOH (5 mL) for 1 h. The mixture was partitioned between CHCl3 and brine. The organic layer was dried (Na2SO4), evaporated, and chromatographed on a silica gel column (hexane/EtOAc=4/1). This gave 8 (892 mg, 83%) as an oil.

Source