Kumiai Chemical Industry Co., Ltd.

Eiichi Hayashi

Kiyoshi Takita

Yukio Nezu

Hironari Sugiyama

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, which is produced by a reaction of dimethyl formamide with chlorosulfonic acid and a dehydrohalogenating agent such as pyridine, triethylamine, dimethyl aniline, which is a tertiary amine so as to produce a sulfate, 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.

Process for producing l-ascorbic acid-2-sulfate

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.

Growing community of inventors

Shizuoka, Japan

Eiichi Hayashi