Potassium Hydroxide → Medica 16

HRID 980031Notes

Reaction equation

HRID 980031 reaction equation
C([O:3][C:4]([CH:6](C(OCC)=O)[C:7]([CH3:33])([CH3:32])[CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][C:18]([CH3:31])([CH3:30])[CH:19](C(OCC)=O)[C:20]([O:22]CC)=[O:21])=[O:5])C.[OH-].[K+]>C(OCC)C>[CH3:30][C:18]([CH3:31])([CH2:17][CH2:16][CH2:15][CH2:14][CH2:13][CH2:12][CH2:11][CH2:10][CH2:9][CH2:8][C:7]([CH3:33])([CH3:32])[CH2:6][C:4]([OH:5])=[O:3])[CH2:19][C:20]([OH:22])=[O:21]

Participants

4

Reactant 2

HCID 14797Potassium HydroxideHCID 14614299HCID 14614299, compound

Product 1

HCID 121871Medica 16

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

A mixture of 17.0 g of the tetra-ester of Example 1 and 300 ml of a 25% aqueous KOH solution was heated in an oil bath to reflux temperature and the mixture was refluxed until the organic phase has completely disappeared (about 48 hours). The aqueous solution was then cooled to room temperature, extracted with ether, further cooled by the addition of ice and acidified with concentrated aqueous hydrochloric acid, whereupon a solid precipitate was formed consisting of the corresponding tetracarboxylic acid. This solid precipitate was dissolved in diethyl ether and the solution dried over anhydrous magnesium sulfate, filtered and evaporated to dryness. The tetracarboxylic acid residue was decarboxylated by heating to 150°-160° C. on an oil bath until evolution of carbon dioxide was no longer observed. The crude product was cooled and recrystallized from a mixture of chloroform and petroleum ether (40°-60° C.). The pure product was obtained at a yield of 5.5 g.

Workup

  1. temperaturewas heated in an oil bath
  2. temperatureto reflux temperature
  3. temperaturethe mixture was refluxed until the organic phase
  4. custom(about 48 hours)
  5. extractionextracted with ether
  6. temperaturefurther cooled by the addition of ice
  7. customwas formed
  8. dry with materialthe solution dried over anhydrous magnesium sulfate
  9. filtrationfiltered
  10. customevaporated to dryness
  11. temperatureby heating to 150°-160° C. on an oil bath until evolution of carbon dioxide
  12. temperatureThe crude product was cooled
  13. customrecrystallized from a mixture of chloroform and petroleum ether (40°-60° C.)
  14. customThe pure product was obtained at a yield of 5.5 g

Sources & evidence

ORD record
ord-1d06a5a9478b444f9cb20b75738e55df
Source dataset
uspto-grants-1987_01
Patent number
US04634795

Reaction notes

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