Реакция #648194

Уравнение реакции

sodium thiosulfate

lithium diisopropylamide

5-[1,3]dioxolan-2-yl-2-fluoro-pyridine

iodine

→

title compound

Выход 60.3%

5-[1,3]Dioxolan-2-yl-2-fluoro-3-iodo-pyridine

Выход 60.3%

Растворители

water

THF

Условия реакции

Обработка

1. 1
   workup.STIRRINGStir for 2 hours
2. 2
   workup.ADDITIONafter the addition
3. 3
   workup.WAITto rise to room temperature over 1 hour
4. 4
   workup.STIRRINGwhile stirring
5. 5
   ЭкстракцияExtract the solution with ether
6. 6
   КонцентрированиеConcentrate the solution in vacuo to a brown oil
7. 7
   ДругоеPurify by column chromatography (hexane to 20% ethyl acetate in hexane)

Методика

Cool a solution of 5-[1,3]dioxolan-2-yl-2-fluoro-pyridine (2.0 g, 11.8 mmol) in THF (20 mL) to −75° C. Add lithium diisopropylamide (2 M in THF, 6 mL, 12 mmol) over a period of 30 min. Stir the mixture for an additional 3 hours. Add iodine (3.0 g, 11.8 mmol, dissolved in 100 mL of THF). Stir for 2 hours after the addition is complete. Add water (100 mL) to the mixture and allow the temperature to rise to room temperature over 1 hour while stirring. Treat the mixture with saturated aqueous sodium thiosulfate solution (50 mL). Extract the solution with ether. Concentrate the solution in vacuo to a brown oil. Purify by column chromatography (hexane to 20% ethyl acetate in hexane) to afford the title compound (2.1 g, 60%) as a yellow oil. MS (ES) m/z 296 [M+1]+.

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