Dimethylformamide → 4-bromo-N-(tert-butyl)-N-methylbenzenesulfonamide

HRID 1867791Notes

Reaction equation

HRID 1867791 reaction equation
[CH3:1]N(C=O)C.[Br:6][C:7]1[CH:12]=[CH:11][C:10]([S:13]([NH:16][C:17]([CH3:20])([CH3:19])[CH3:18])(=[O:15])=[O:14])=[CH:9][CH:8]=1.IC.C([O-])([O-])=O.[K+].[K+]>C(OCC)(=O)C.O>[Br:6][C:7]1[CH:8]=[CH:9][C:10]([S:13]([N:16]([C:17]([CH3:20])([CH3:19])[CH3:18])[CH3:1])(=[O:15])=[O:14])=[CH:11][CH:12]=1

Participants

7

Reactant 4

HCID 6228DimethylformamideHCID 6328Methyl iodideHCID 11430Potassium CarbonateHCID 796629N-t-Butyl 4-bromobenzenesulfonamide

Product 1

HCID 579800364-bromo-N-(tert-butyl)-N-methylbenzenesulfonamideYield 97%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Procedure

Procedure R′: A 15 m-1L DMF mixture of 4-bromo-N-tert-butyl-benzenesulfonamide (1022 mg, 3.5 mmol), iodomethane (0.44 mL, 7 mmol), and K2CO3 (987 mg, 7 mmol) is stirred at room temperature overnight. Water and ethyl acetate are added to the mixture. The aqueous layer is extracted several times with ethyl acetate. The combined organic layers are washed with H2O and brine, then dried over Na2SO4 and evaporated. The crude product is purified by silica-gel column chromatography (gradient: 100% CH2Cl2 to 20% EtOAc/CH2Cl2) give the intermediate 4-bromo-N-tert-butyl-N-methyl-benzenesulfonamide (1040 mg, 97% yield). MS (ES+) 251.9 (M-tBu)+, NMR (CDCl3).

Workup

  1. extractionThe aqueous layer is extracted several times with ethyl acetate
  2. washThe combined organic layers are washed with H2O and brine
  3. dry with materialdried over Na2SO4
  4. customevaporated
  5. customThe crude product is purified by silica-gel column chromatography (gradient: 100% CH2Cl2 to 20% EtOAc/CH2Cl2)

Sources & evidence

ORD record
ord-7f84d99500be4e29a8ddd98ab8b8f6c7
Source dataset
uspto-grants-2009_12
Patent number
US07632857B2

Reaction notes

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