Dimethylformamide → 4-acetyl-1-methyl-1H-pyrrole-2-carbonitrile

HRID 1436465Notes

Reaction equation

HRID 1436465 reaction equation
[CH3:1][N:2]1[CH:6]=[CH:5][C:4]([C:7](=[O:9])[CH3:8])=[CH:3]1.ClS([N:14]=[C:15]=O)(=O)=O.CN(C)C=O.C(=O)([O-])[O-].[Na+].[Na+]>ClCCl.O>[C:7]([C:4]1[CH:5]=[C:6]([C:15]#[N:14])[N:2]([CH3:1])[CH:3]=1)(=[O:9])[CH3:8]

Participants

7

Reactant 4

HCID 6228DimethylformamideHCID 10340Sodium CarbonateHCID 70918Chlorosulfonyl isocyanateHCID 5230573-Acetyl-1-methylpyrrole

Product 1

HCID 141738634-acetyl-1-methyl-1H-pyrrole-2-carbonitrileYield 51.9%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent

Procedure

To a solution of 1-methyl-3-acetylpyrrole (4.0 g, 32.5 mmol) in dry dichloromethane (40 mL), under nitrogen at −78° C., was added chlorosulfonyl isocyanate (2.8 mL, 32.5 mmol) dropwise. The reaction warmed to room temperature over 2 h, and was then treated with dimethylformamide (8 mL). After 30 min, the reaction was poured into water, treated with a 1 N sodium carbonate solution (10 mL) and extracted with methylene chloride (2×50 mL). The combined organic layers were washed with water, dried (anhydrous sodium sulfate) and evaporated. The residue was purified by silica gel column chromatography (ethyl acetate:hexanes, 3:1 to 1:1) to afford 4-acetyl-1-methyl-1H-pyrrole-2-carbonitrile (2.5 g, 16.87 mmol), which was used without further characterization.

Workup

  1. extractionextracted with methylene chloride (2×50 mL)
  2. washThe combined organic layers were washed with water
  3. dry with materialdried (anhydrous sodium sulfate)
  4. customevaporated
  5. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexanes, 3:1 to 1:1)

Sources & evidence

ORD record
ord-4e5ef68cdb404247963f6340d3a334ee
Source dataset
uspto-grants-2009_11
Patent number
US07618990B2

Reaction notes

Loading…