Reaction #56600

Reaction equation

dry ice

thymidine

triphenylphosphine

diisopropylazodicarboxylate

→

white solid

Yield 83.0%

Anhydrothymidine

Yield 83.0%

Solvents

H2O

iPrOH

CH3CN

CH3CN

Conditions

Workup

1. 1
   workup.ADDITIONAfter the addition
2. 2
   Temperatureto warm to 10° C. over a period of 5 hours
3. 3
   OtherThe reaction was then quenched with H2O (6 mL)
4. 4
   Otherforming a white suspension
5. 5
   workup.WAITto stand for 30 minutes
6. 6
   Filtrationwas filtered
7. 7
   WashThe collected solid was washed with cold CH3CN
8. 8
   Otherdried under vacuum

Procedure

To a dried round bottom flask containing thymidine(10.0 g, 41.6 mmol) was added triphenylphosphine (21.8 g, 82.2 mmol) and CH3CN (160 mL). The suspension was cooled to −20° C. ((40:60 iPrOH:H2O) and dry ice). To the reaction mixture was added diisopropylazodicarboxylate (16.8 g, 82.2 mmol) as CH3CN solution (60 mL) dropwise via an addition funnel, over a period of 1 hour. After the addition, the mixture was stirred for an additional 90 minutes at 20° C. The mixture was allowed to warm to 10° C. over a period of 5 hours. The reaction was then quenched with H2O (6 mL) forming a white suspension. The reaction was allowed to stand for 30 minutes and then was filtered. The collected solid was washed with cold CH3CN and dried under vacuum to afford 7.7 g (83% yield) of a white solid. If desired, the solid may be recrystallized in EtOH.

Source