Diisopropylethylamine → 1-methanesulfonyl-3-methyl-6-nitro-1H-indole

HRID 1106783Notes

Reaction equation

HRID 1106783 reaction equation
[CH2:1]([N:4]([C:9]1[CH:14]=[C:13]([N+:15]([O-:17])=[O:16])[CH:12]=[CH:11][C:10]=1Br)[S:5]([CH3:8])(=[O:7])=[O:6])[CH:2]=[CH2:3].C(N(C(C)C)CC)(C)C>C1(C)C=CC=CC=1.C([O-])(=O)C.[Pd+2].C([O-])(=O)C>[CH3:8][S:5]([N:4]1[C:9]2[C:10](=[CH:11][CH:12]=[C:13]([N+:15]([O-:17])=[O:16])[CH:14]=2)[C:2]([CH3:3])=[CH:1]1)(=[O:7])=[O:6]

Participants

5

Reactant 2

HCID 81531DiisopropylethylamineHCID 18789667N-allyl-N-(2-bromo-5-nitrophenyl)methanesulfonamide

Product 1

HCID 187896701-methanesulfonyl-3-methyl-6-nitro-1H-indoleYield 63%

Reagents, catalysts & solvents 2

HCID 167845palladium(II) acetateCatalystHCID 1140TolueneSolvent

Procedure

According to the method of Martin, Helv. Chem. Acta. (1989) 72:1554, a mixture of N-allyl-N-(2-bromo-5-nitrophenyl)methanesulfonamide (2.45 g, 7.31 mmol), palladium acetate (83 mg, 0.37 mmol), tri-o-tolyl phoshpine (222 mg, 0.73 mmol) and diisopropylethylamine (1.42 g, 11.0 mmol) in 10 ml of toluene was heated to reflux for 18 hr. The reaction was cooled and filtered through a fine Whatman glass fiber filter to remove the palladium. The mixture was diluted with 100 ml of ethyl acetate, then washed successively with 1M HCl (50 ml) and brine. The extracts were dried (anhydrous MgSO4) and concentrated. The crude product was dissolved in acetone. Silica gel (10 g) was added then the solvent was removed at reduced pressure. The resultant powder was applied to silica gel column (110 g) and eluted with 25% ethyl acetate/hexane to give 1.17 g of 1-methanesulfonyl-3-methyl-6-nitro-1H-indole (63% yield).

Workup

  1. temperaturewas heated
  2. temperatureto reflux for 18 hr
  3. temperatureThe reaction was cooled
  4. filtrationfiltered through a fine Whatman glass fiber
  5. filtrationfilter
  6. customto remove the palladium
  7. additionThe mixture was diluted with 100 ml of ethyl acetate
  8. washwashed successively with 1M HCl (50 ml) and brine
  9. dry with materialThe extracts were dried (anhydrous MgSO4)
  10. concentrationconcentrated
  11. dissolutionThe crude product was dissolved in acetone
  12. additionSilica gel (10 g) was added
  13. customthe solvent was removed at reduced pressure
  14. washeluted with 25% ethyl acetate/hexane

Sources & evidence

ORD record
ord-ef1945131d2249238643934bef4805ce
Source dataset
uspto-grants-2000_05
Patent number
US06057349

Reaction notes

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