Water → HCID 19036596, compound

HRID 264522Notes

Reaction equation

HRID 264522 reaction equation
[N:1]1([CH2:14][CH2:15][NH:16][C:17](=[O:19])[CH3:18])[CH:5]=[CH:4][C:3]2[CH2:6][O:7][C:8]3[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=3[C:2]1=2.[OH-:20].[K+].[OH2:22].[Cl-].[Na+].C([O:27][CH2:28][CH3:29])C>C(O)CO>[C:28]([OH:27])(=[O:22])/[CH:29]=[CH:18]/[C:17]([OH:19])=[O:20].[N:1]1([CH2:14][CH2:15][NH2:16])[CH:5]=[CH:4][C:3]2[CH2:6][O:7][C:8]3[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=3[C:2]1=2

Participants

7

Reactant 5

HCID 962WaterHCID 3283Diethyl EtherHCID 5234Sodium ChlorideHCID 14797Potassium HydroxideHCID 19036429HCID 19036429, compound

Product 1

HCID 19036596HCID 19036596, compoundYield 31%

Reagents, catalysts & solvents 1

HCID 174Ethylene GlycolSolvent

Procedure

A mixture of 2.5 g of N-[2-(1,4-dihydro[1]benzopyrano[4,3-b]pyrrol-1-yl)-ethyl]-acetamide, 3.28 g of potassium hydroxide, 20 ml of water and 40 ml of ethylene glycol was heated to 110° while stirring for 23 hours. After cooling, the reaction mixture was poured into 100 ml of saturated sodium chloride solution and extracted three times with 200 ml of ethyl acetate each time. The organic phases were washed once with 200 ml of saturated sodium chloride solution, dried over magnesium sulfate and concentrated in a vacuum. The residue was purified by column chromatography on silica gel (dichloromethane/methanol/ammonia 200:10:1). The oil obtained was dissolved in 110 ml of anhydrous diethyl ether, filtered and treated with a solution of 436 mg of fumaric acid in 20 ml of anhydrous methanol. The mixture was stirred at room temperature for 18 hours and the white crystals were subsequently filtered off under suction. 812 mg (31%) of 2-(1,4-dihydro-[1]benzopyrano[4,3-b]pyrrol-1-yl)-ethylamine fumarate (1:0.5) with m.p. 180° were obtained.

Workup

  1. temperaturewas heated to 110°
  2. temperatureAfter cooling
  3. extractionextracted three times with 200 ml of ethyl acetate each time
  4. washThe organic phases were washed once with 200 ml of saturated sodium chloride solution
  5. dry with materialdried over magnesium sulfate
  6. concentrationconcentrated in a vacuum
  7. customThe residue was purified by column chromatography on silica gel (dichloromethane/methanol/ammonia 200:10:1)
  8. customThe oil obtained
  9. filtrationfiltered
  10. additiontreated with a solution of 436 mg of fumaric acid in 20 ml of anhydrous methanol
  11. stirringThe mixture was stirred at room temperature for 18 hours
  12. filtrationthe white crystals were subsequently filtered off under suction

Sources & evidence

ORD record
ord-504e5f6982444b0a93464c55ab975dd2
Source dataset
uspto-grants-1997_07
Patent number
US05646173

Reaction notes

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