Wohl degradation

The Wohl degradation in carbohydrate chemistry is a chain contraction method for aldoses.

The reaction is named after the German chemist Alfred Wohl (1863–1939).

In one modification,[2][3] d-glucose is converted to the glucose oxime by reaction with hydroxylamine and sodium methoxide.

In the final step sodium methoxide in methanol is added, leading to removal of all the acetate groups and ejection of the nitrile group and collapse of the second carbon from a tetrahedral structure to an aldehyde.

Fenton 1893) converts the aldose first to the alpha-hydroxy-carboxylic acid with bromine and calcium hydroxide and then to the shortened aldose by reaction with Iron(III) sulfate and hydrogen peroxide.