Question

Oxidation of fructose with nitric acid gives glycolic acid and tartaric acid. What information that this reaction gives to establish the structure of fructose.

Answer 1

On oxidation with nitric acid, it gives glycolic acid and tartaric acids which contain smaller number of carbon atoms than in fructose.

This shows that a keto group is present in C₂. It also shows the presence of 1° alcoholic groups at C₁ and C₆.