Reaction #40583

Reaction equation

calcium carbonate

benzyltrimethylammonium dichloroiodate

5-amino-2-chloropyridine

→

expected product

Yield 39.1%

3-Amino-6-chloro-2-iodopyridine

Yield 39.1%

Solvents

methanol

dichloro-methane

Conditions

Workup

1. 1
   Filtrationfiltered
2. 2
   Otherto remove the mineral salts
3. 3
   workup.ADDITIONThe filtrate is diluted with water
4. 4
   Extractionextracted with DCM
5. 5
   OtherThe organic phase obtained
6. 6
   Washis washed with sodium chloride solution
7. 7
   Dryingwith saturated sodium thiosulfate solution, dried over magnesium sulfate
8. 8
   Concentrationconcentrated under reduced pressure
9. 9
   OtherAn oil is obtained
10. 10
    Otherwhich is purified by chromatography on silica gel
11. 11
    Washeluting with a cyclohexane/ethyl acetate mixture (80/20

Procedure

23.2 g (180.5 mM) of 5-amino-2-chloropyridine are mixed in 70 ml of dichloro-methane (DCM) and 180 ml of methanol, and 21.6 g (216 mM) of calcium carbonate and 75.3 g (226 mM) of benzyltrimethylammonium dichloroiodate are added. The reaction mixture is stirred at room temperature for 16 hours, and then filtered to remove the mineral salts. The filtrate is diluted with water and extracted with DCM. The organic phase obtained is washed with sodium chloride solution, and then with saturated sodium thiosulfate solution, dried over magnesium sulfate and concentrated under reduced pressure. An oil is obtained, which is purified by chromatography on silica gel, eluting with a cyclohexane/ethyl acetate mixture (80/20 and then 70/30; v/v). 13.9 g of the expected product are thus obtained in the form of an orange-colored solid (yield=30%).

Source