Reacción #4982

Ecuación de reacción

2', 3'-dideoxycytidine

Iodine

→

iodide

Rendimiento 83.0%

5-iodo-2', 3'-dideoxycytidine

Rendimiento 83.0%

Disolventes

methanol

methanol

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONthe free base form of AG3 X4A resin (20 mL, 38 meq, Bio-Rad) was added
2. 2
   Otrohydrogen sulfide was bubbled into the reaction for 15 minutes
3. 3
   OtroComplete precipitation of mercury(II)
4. 4
   FiltraciónThe reaction was filtered
5. 5
   Filtraciónthrough filter aid
6. 6
   Lavadothe filter aid was washed with 1:1 methanol-dichloromethane
7. 7
   OtroThe filtrate was evaporated onto silica gel (10 g)
8. 8
   LavadoElution

Procedimiento

A solution of 2', 3'-dideoxycytidine (2.11 g, 10 mmol, Raylo) and mercuric acetate (3.35 g, 10.5 mmol, Fisher) in 50 mL of methanol was refluxed for 19 hours. The resulting white suspension was diluted with methanol (50 mL) and dichloromethane (100 mL). Iodine (3.05 g, 12 mmol) was added and the suspension was stirred at 25°. After 4 hours, the free base form of AG3 X4A resin (20 mL, 38 meq, Bio-Rad) was added and hydrogen sulfide was bubbled into the reaction for 15 minutes. Complete precipitation of mercury(II) was verified by TLC. The reaction was filtered through filter aid and the filter aid was washed with 1:1 methanol-dichloromethane. The filtrate was evaporated onto silica gel (10 g) and the loaded siliva gel was placed on top of a 150 g silica gel column. Elution was 5%, 10%, and 20% methanol in dichloromethane afforded 2.79 g (83%) of iodide 19 as a colorless crystalline solid. Two recrystallizations form boiling water afforded, after vacuum-drying at 50°, large, analytically-pure prisms (mp: d 178° ).

Fuente