Iodine → 4-(4-Iodo-3-nitrophenyl)-1-methyl-1H-pyrazole

HRID 1435110Notes

Reaction equation

HRID 1435110 reaction equation
[I:1]I.N(OCCCC)=O.[CH3:10][N:11]1[CH:15]=[C:14]([C:16]2[CH:22]=[CH:21][C:19](N)=[C:18]([N+:23]([O-:25])=[O:24])[CH:17]=2)[CH:13]=[N:12]1.S([O-])([O-])=O.[Na+].[Na+]>C(Cl)Cl.CS(C)=O.C(#N)C>[I:1][C:19]1[CH:21]=[CH:22][C:16]([C:14]2[CH:13]=[N:12][N:11]([CH3:10])[CH:15]=2)=[CH:17][C:18]=1[N+:23]([O-:25])=[O:24]

Participants

8

Reactant 4

HCID 807IodineHCID 10996Butyl nitriteHCID 24437Sodium SulfiteHCID 57937593HCID 57937593, compound

Product 1

HCID 579375394-(4-Iodo-3-nitrophenyl)-1-methyl-1H-pyrazoleYield 95%

Reagents, catalysts & solvents 3

HCID 679Dimethyl SulfoxideSolventHCID 6342AcetonitrileSolventHCID 6344DichloromethaneSolvent

Procedure

Iodine (3.5 g, 14 mmol), acetonitrile (40 ml), and test-butyl nitrite (0.82 mL, 6.9 mmol) were combined under N2 in a 3-neck round bottom flask fitted with reflux condenser and an addition funnel. The mixture was stirred at rt. To the addition funnel was added a solution of 4-(1-methyl-1H-pyrazol-4-yl)-2-nitroaniline (1.0 g, 4.6 mmol) dissolved in DCM (20 mL) and DMSO (2 mL). This solution was added dropwise to flask at rt. The reaction was placed in a 60° C. oil bath and after 5-10 minutes bubbles began appearing. The reaction was stirred for an additional 2 h at 60° C. and then the heat was turned off and the reaction stirred at rt overnight. Aqueous sodium sulfite solution was added and the mixture was extracted with EtOAc (3×). Combined organic layers were dried over anhydrous MgSO4, filtered, concentrated onto silica gel and purified by flash chromatography using 20-60% EtOAc/hexanes. 1.43 g (95%) of 4-(4-iodo-3-nitrophenyl)-1-methyl-1H-pyrazole was isolated as a yellow solid. MS (ESI): 330, 331 [M+H]+.

Workup

  1. customwere combined under N2 in a 3-neck round bottom flask
  2. customfitted
  3. temperaturewith reflux condenser and an addition funnel
  4. additionThis solution was added dropwise to flask at rt
  5. customwas placed in a 60° C.
  6. stirringThe reaction was stirred for an additional 2 h at 60° C.
  7. stirringthe reaction stirred at rt overnight
  8. extractionthe mixture was extracted with EtOAc (3×)
  9. dry with materialCombined organic layers were dried over anhydrous MgSO4
  10. filtrationfiltered
  11. concentrationconcentrated onto silica gel
  12. custompurified by flash chromatography

Sources & evidence

ORD record
ord-ae459d520d9f4de2ba92b2a30ec0bac9
Source dataset
uspto-grants-2009_11
Patent number
US07615643B2

Reaction notes

Loading…