Reaktion #535899

Reaktionsgleichung

ammonium chloride

butyl lithium

compound

4-Acetylamino-5-bromo-7-(2,3,5-tri-O-acetyl-2-C-methyl-β-D-ribofuranosyl)-7H-pyrrolo[2,3-d]pyrimidine

N-fluorobenzensulfonimide

→

desired product

4-Amino-5-fluoro-7-(2-C-methyl-β-D-ribofuranosyl)-7H-pyrrolo[2,3-d]pyrimidine

Lösungsmittel

dichloromethane

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeto come to ambient temperature
2. 2
   SonstigeThe organic phase is evaporated in vacuo
3. 3
   workup.ADDITIONtreated with ammonium hydroxide at 55° C. in a closed container overnight
4. 4
   SonstigeThe resulting crude mixture is purified on silica gel
5. 5
   workup.ADDITIONFractions containing the desired product
6. 6
   Sonstigeevaporated in vacuo

Vorschrift

To a pre-cooled (−78° C.) solution of the compound from Step B (529 mg, 1.00 mmol) in THF is added butyl lithium (2M in hexanes) (0.5 mL, 1.00 mmol). The resulting solution is stirred at −78° C. for 30 min and then quenched with N-fluorobenzensulfonimide (315 mg, 1.00 mmol) in THF. The resulting solution is very slowly allowed to come to ambient temperature and then poured into a stirred mixture of saturated aqueous ammonium chloride and dichloromethane. The organic phase is evaporated in vacuo and treated with ammonium hydroxide at 55° C. in a closed container overnight. The resulting crude mixture is purified on silica gel using dichloromethane/methanol as the eluent. Fractions containing the desired product are pooled and evaporated in vacuo to give the desired product.

Quelle