Potassium Hydroxide → 1-Amino-3-benzoylpyrrole

HRID 1080473Notes

Reaction equation

HRID 1080473 reaction equation
[C:1]([C:9]1[CH:13]=[CH:12][NH:11][CH:10]=1)(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[OH-].[K+].[NH2:16]OS(O)(=O)=O>CN(C)C=O.O>[NH2:16][N:11]1[CH:12]=[CH:13][C:9]([C:1]([C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=2)=[O:8])=[CH:10]1

Participants

6

Reactant 3

HCID 14797Potassium HydroxideHCID 76284hydroxylamine-O-sulfonic acidHCID 27732343-Benzoylpyrrole

Product 1

HCID 199731561-Amino-3-benzoylpyrrole

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

To a solution of 3-benzoylpyrrole (4.92 g) in 50 ml of dry dimethylformamide was added milled potassium hydroxide (8.06 g). Hydroxylamine-O-sulfonic acid (4.23 g) was added to the suspension in 4 portions over a period of 1 hour with stirring at room temperature. After the addition was completed the reaction mixture was stirred for 30 minutes at room temperature, and subsequently diluted with 50 ml of water and extracted with DCM. The combined organic layers were washed with water, dried over magnesium sulfate and evaporated in vacuo. The residue was purified by flash column chromatography (silica gel, DCM/ethyl acetate, 5:1), affording starting material (1.44 g) and the desired product as the second fraction. Recrystallization from ethyl ether/hexane gave the product as crystals (1.80 g), which was combined with material obtained from a 36.9 mmol scale reaction and recryslized from DCM/hexane affording 3.20 g of crystals, m.p. 82°-83° C.

Workup

  1. additionAfter the addition
  2. stirringwas stirred for 30 minutes at room temperature
  3. extractionextracted with DCM
  4. washThe combined organic layers were washed with water
  5. dry with materialdried over magnesium sulfate
  6. customevaporated in vacuo
  7. customThe residue was purified by flash column chromatography (silica gel, DCM/ethyl acetate, 5:1)
  8. customaffording

Sources & evidence

ORD record
ord-7db952eb88b448f5916e83519562f4e9
Source dataset
uspto-grants-1996_12
Patent number
US05580987

Reaction notes

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