Reichstein process

The Reichstein process in chemistry is a combined chemical and microbial method for the production of ascorbic acid from D-glucose that takes place in several steps. This process was devised by Nobel Prize winner Tadeus Reichstein and his colleagues in 1933 while working in the laboratory of the ETH in Zürich.

The reaction steps are:

The microbial oxidation of sorbitol to sorbose is important because it provides the correct stereochemistry.

This process was patented and sold to Hoffmann-La Roche in 1935. The first commercially sold vitamin C product was called Cebion from Merck.

Even today all industrial methods for the production of ascorbic acid are based on the Reichstein process. In modern methods however, sorbose is directly oxidized with a platinum catalyst (developed by Kurt Heyns (1908–2005) in 1942). This method avoids the use of protective groups. A side product with particular modification is 5-Keto-D-gluconic acid.

Novel methods involve genetically modified bacteria.

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