Process for producing L-ascorbic acid-2-sulfate
AssigneeKumiai Chemical Industry Co., Ltd.
InventorsEiichi Hayashi, Kiyoshi Takita, Hironari Sugiyama, Yukio Nezu
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Abstract
A process for producing a mono- or di-alkali metal salt or alkaline earth metal salt of L-ascorbic acid-2-sulfate which comprises reacting L-ascorbic acid in which the 5 and 6 positions are protected by a ketone or aldehyde, with dimethyl formamide-sulfur trioxide complex, and neutralizing the product with an alkali metal hydroxide or an alkaline earth metal hydroxide, and removing said protecting aldehyde or ketone at 5-and 6-positions.
Claims7
A process for producing a mono- or di-alkali metal salt or alkaline earth metal salt of L-ascorbic acid-2-sulfate which consists essentially of:
- A. reacting L-ascorbic acid in which the 5- and 6- positions are protected by a ketone or aldehyde, with dimethyl formamide-sulfur trioxide complex in an inert solvent,
- B. neutralizing the product with an alkali metal hydroxide or an alkaline earth metal hydroxide, and
- C. removing said protecting aldehyde or ketone at the 5-and 6-positions.
Dependencies are inferred from the claim text.