Hydrochloric Acid → 2-(4-Fluoro-2,3-dihydroxyphenyl)-2-hydroxyacetic acid

HRID 2572

Reaction equation

HRID 2572 reaction equation
[F:1][C:2]1[CH:8]=[CH:7][CH:6]=[C:4]([OH:5])[C:3]=1[OH:9].[C:10]([OH:14])(=[O:13])[CH:11]=[O:12].[OH-].[Na+].Cl>O>[F:1][C:2]1[CH:8]=[CH:7][C:6]([CH:11]([OH:12])[C:10]([OH:14])=[O:13])=[C:4]([OH:5])[C:3]=1[OH:9]

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 760Glyoxylic AcidHCID 14798Sodium HydroxideHCID 677643-Fluorocatechol

Product 1

HCID 183591842-(4-Fluoro-2,3-dihydroxyphenyl)-2-hydroxyacetic acidYield 59%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Conditions

Temperature
0 °C

Procedure

51.2 g of 3-fluorocatechol and 36.8 g of glyoxylic acid were dissolved at 20° C. in 160 ml of water and 34.8 g of sodium hydroxide in solution in 400 ml of water were added to this solution cooled to 0° C. The mixture was heated for 4 hours at 46° C., then cooled to 0° C. and the pH was brought to 4.6 by the addition of concentrated hydrochloric acid. Extraction was carried out with ethyl ether (after evaporation 14.7 g of the starting 9-fluorocatechol were collected) and the aqueous phase was acidified with concentrated hydrochloric acid until a pH of 1.8 was obtained. Extraction was carried out with ethyl acetate and after evaporation of the solvent, 47.7 g of the desired product were obtained (mixture of isomers, 2,3-bis-hydroxy-4-fluoro; 3,4-bis-hydroxy-5-fluoro; 2-fluoro-3,4-bis-hydroxy) which was used as is in Step A of Example 16.

Workup

  1. temperatureThe mixture was heated for 4 hours at 46° C.
  2. temperaturecooled to 0° C.
  3. extractionExtraction
  4. customwas carried out with ethyl ether (after evaporation 14.7 g of the starting 9-fluorocatechol were collected)
  5. customwas obtained
  6. extractionExtraction
  7. customafter evaporation of the solvent

Sources & evidence

ORD record
ord-9cad495ca4824beabdad8a4e8de68a2c
Source dataset
uspto-grants-1998_03
Patent number
US05728828

Linked notes

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