Iodine → 1-(4-chlorophenyl)-3-[(Z)-3-iodobut-2-enoxy]pyrazole

HRID 918756Notes

Reaction equation

HRID 918756 reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[CH:12]=[CH:11][C:10]([O:13][CH2:14]/[CH:15]=[C:16](\[Sn](CCCC)(CCCC)CCCC)/[CH3:17])=[N:9]2)=[CH:4][CH:3]=1.[I:31]I>C(Cl)Cl>[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[CH:12]=[CH:11][C:10]([O:13][CH2:14]/[CH:15]=[C:16](\[I:31])/[CH3:17])=[N:9]2)=[CH:4][CH:3]=1

Participants

4

Reactant 2

HCID 807IodineHCID 1317348731-(4-Chloro-phenyl)-3-((Z)-3-tributylstannanyl-but-2-enyloxy)-1H-pyrazole

Product 1

HCID 896503821-(4-chlorophenyl)-3-[(Z)-3-iodobut-2-enoxy]pyrazole

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To 10.0 g (18.6 mmol) 1-(4-chloro-phenyl)-3-((Z)-3-tributylstannanyl-but-2-enyloxy)-1H-pyrazole in 100 ml methylene chloride have been added 4.7 g (18.6 mmol) iodine at ambient temperature with stirring which was continued for 3 h. After removal of the solvents in vacuo the crude product was dissolved in 200 ml MTBE. 100 ml 20% aqueous potassium fluoride solution have been added and the mixture was stirred for 2 h at ambient temperature. The aqueous layer was separated and extracted with 20 ml methyl-tert.-butyl ether twice. The combined organic phases have been washed twice with 20 ml of water each, dried with sodium sulfate, and the solvents were removed in vacuo. The crude product (7.2 g) has been purified by chromatography on 50 g silica with methyl-tert.-butylether/hexane (1:20). Yield 5.9 g, melting point 75-77° C.

Workup

  1. customAfter removal of the solvents in vacuo the crude product
  2. dissolutionwas dissolved in 200 ml MTBE
  3. addition100 ml 20% aqueous potassium fluoride solution have been added
  4. stirringthe mixture was stirred for 2 h at ambient temperature
  5. customThe aqueous layer was separated
  6. extractionextracted with 20 ml methyl-tert.-butyl ether twice
  7. washThe combined organic phases have been washed twice with 20 ml of water each,
  8. dry with materialdried with sodium sulfate
  9. customthe solvents were removed in vacuo
  10. customThe crude product (7.2 g) has been purified by chromatography on 50 g silica with methyl-tert.-butylether/hexane (1:20)

Sources & evidence

ORD record
ord-d2ca9fdf88b74a30b3c38ffecb6e04e9
Source dataset
uspto-grants-2016_03
Patent number
US09271501B2

Reaction notes

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