Hydrochloric Acid → L-Ascorbic Acid

HRID 2412350Notes

Reaction equation

HRID 2412350 reaction equation
Cl.[Na].[CH2:3]([OH:15])[C@H:4]([OH:14])[C@@H:5](O)[C@H:6]([OH:12])[C:7]([C:9]([O-:11])=[O:10])=[O:8]>>[O:10]=[C:9]1[O:11][C@H:5]([C@H:4]([CH2:3][OH:15])[OH:14])[C:6]([OH:12])=[C:7]1[OH:8]

Participants

3

Reactant 2

HCID 313Hydrochloric AcidHCID 131714077HCID 131714077, compound

Product 1

HCID 54670067L-Ascorbic Acid

Procedure

L-ascorbic acid is prepared from sodium 2-keto-L-gulonate by introducing gaseous hydrogen chloride in a molar ratio of about 1.5-2.0 to the sodium-2-keto-L-gulonate into a mixture composed of the sodium 2-keto-L-gulonate, ethanol and acetone at a ratio of 1:0.25-1.00:0.5-2.5 by weight at a temperature of about 25°-75° C. until precipitation of sodium chloride ends, removing the precipitated sodium chloride before L-ascorbic acid begins to crystalize out, maintaining the filtrate or supernatant at a temperature of about 25°-75° C. for a period of 5-100 hours and cooling it to yield crystals of L-ascorbic acid as a final product. A solvent inert to the L-ascorbic acid and 2-keto-L-gulonate may be added to the filtrate or supernatant with a favorable result in obtaining purer intended product.

Workup

  1. customcomposed of the sodium 2-keto-L-gulonate, ethanol and acetone at a ratio of 1:0.25-1.00:0.5-2.5 by weight at a temperature of about 25°-75° C. until precipitation of sodium chloride
  2. customremoving the precipitated sodium chloride before L-ascorbic acid
  3. customto crystalize out
  4. temperaturemaintaining the filtrate or supernatant at a temperature of about 25°-75° C. for a period of 5-100 hours
  5. temperaturecooling it

Sources & evidence

ORD record
ord-de0b71ae10d044409b6261710b7fe69a
Source dataset
uspto-grants-1985_01
Patent number
US04491668

Reaction notes

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