反应详情

A suspension of 9.0 g of 3-iodo-5-(methylsulfonyl)-2(1H)-pyridinone in 30 ml of phosphorus oxychloride was refluxed under nitrogen for 4 hours and gave a homogeneous mixture. This solidified on cooling and unreacted phosphorus oxychloride was removed under reduced pressure. The resulting white solid residue was dissolved in methylene chloride and extracted first with water and twice with aqueous 1N sodium hydroxide solution. The mixture was shaken until the aqueous phase remained basic. The methylene chloride solution was then dried over magnesium sulfate and concentrated to leave a white solid residue. This was recrystallized from ethyl acetate/hexane to give 2-chloro-3-iodo-5-(methylsulfonyl)pyridine as colorless needles melting at about 178.5°-180.5° C.

1. temperaturewas refluxed under nitrogen for 4 hours
2. customgave a homogeneous mixture
3. temperatureon cooling
4. customunreacted phosphorus oxychloride was removed under reduced pressure
5. dissolutionThe resulting white solid residue was dissolved in methylene chloride
6. extractionextracted first with water and twice with aqueous 1N sodium hydroxide solution
7. dry with materialThe methylene chloride solution was then dried over magnesium sulfate
8. concentrationconcentrated
9. customto leave a white solid residue
10. customThis was recrystallized from ethyl acetate/hexane