Iodine → 3,5-diethyl 4-iodo-1H-pyrazole-3,5-dicarboxylate

HRID 33274

Reaction equation

HRID 33274 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[CH:10]=[C:9]([C:11]([O:13][CH2:14][CH3:15])=[O:12])[NH:8][N:7]=1)=[O:5])[CH3:2].[I:16]I.S([O-])([O-])(=O)=S.[Na+].[Na+]>C(#N)C>[CH2:14]([O:13][C:11]([C:9]1[C:10]([I:16])=[C:6]([C:4]([O:3][CH2:1][CH3:2])=[O:5])[NH:7][N:8]=1)=[O:12])[CH3:15]

Participants

5

Reactant 3

HCID 807IodineHCID 24477Sodium ThiosulfateHCID 142184diethyl 1H-pyrazole-3,5-dicarboxylate

Product 1

HCID 117392303,5-diethyl 4-iodo-1H-pyrazole-3,5-dicarboxylate

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

To a solution of 10 g 1H-Pyrazole-3,5-dicarboxylic acid diethyl ester in 400 ml acetonitrile 13 g ammonium cerium(iv) nitrate (CAN) and 7.17 g iodine were added and the mixture was heated to reflux for 5 h. Then, after cooling to RT, 30 ml sat. sodium thiosulfate solution were added. The mixture was extracted with ethyl acetate (3×100 ml), the combined organic layers were washed with water and then dried over MgSO4, filtered and the solvents were removed under reduced pressure. The residue was filtered through a pad of silica gel eluting with heptane/ethyl acetate 1:1.

Workup

  1. temperaturethe mixture was heated
  2. temperatureto reflux for 5 h
  3. extractionThe mixture was extracted with ethyl acetate (3×100 ml)
  4. washthe combined organic layers were washed with water
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. customthe solvents were removed under reduced pressure
  8. filtrationThe residue was filtered through a pad of silica gel eluting with heptane/ethyl acetate 1:1

Sources & evidence

ORD record
ord-0d5a393a7b0d42febfff4291922d7261
Source dataset
uspto-grants-2008_09
Patent number
US07429581B2

Linked notes

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