Ethanol → 10H-Pyrazino[2,3-b][1,4]benzothiazine-8-acetic acid

HRID 1059363Notes

Reaction equation

HRID 1059363 reaction equation
[N:1]1[C:10]2[NH:9][C:8]3[CH:11]=[C:12](CC#N)[CH:13]=[CH:14][C:7]=3[S:6][C:5]=2[N:4]=[CH:3][CH:2]=1.[OH-:18].[K+].[CH2:20]([OH:22])[CH3:21]>>[N:1]1[C:10]2[NH:9][C:8]3[CH:11]=[C:12]([CH2:21][C:20]([OH:18])=[O:22])[CH:13]=[CH:14][C:7]=3[S:6][C:5]=2[N:4]=[CH:3][CH:2]=1

Participants

4

Reactant 3

HCID 702EthanolHCID 14797Potassium HydroxideHCID 1867021210H-Pyrazino[2,3-b][1,4]benzothiazine-8-acetonitrile

Product 1

HCID 1867013310H-Pyrazino[2,3-b][1,4]benzothiazine-8-acetic acid

Procedure

4.7 g of 10H-pyrazino[2,3-b][1,4]benzothiazine-8-acetonitrile was dissolved in 100 ml of ethanol. After adding 2.8 g of potassium hydroxide, the resulting mixture was heated under reflux for 16 hours. After distilling off the ethanol, water was added and the mixture was made weakly acidic with dilute hydrochloric acid followed by the extraction with ethyl acetate and dichloromethane. The organic layer was dried over anhydrous magnesium sulfate. After distilling off the solvent under reduced pressure, 3.85 g of the title compound was obtained as yellow crystals.

Workup

  1. temperaturethe resulting mixture was heated
  2. temperatureunder reflux for 16 hours
  3. distillationAfter distilling off the ethanol, water
  4. additionwas added
  5. extractionfollowed by the extraction with ethyl acetate and dichloromethane
  6. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
  7. distillationAfter distilling off the solvent under reduced pressure

Sources & evidence

ORD record
ord-83a41f4c3c7541cfbf9f4b24353f30cd
Source dataset
uspto-grants-2003_02
Patent number
US06518423B1

Reaction notes

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