Chemistry of pongamol. Part I

Summary

Pongamol, which is the second important crystalline component of the pongamia oil, has the molecular formula C₁₈H₁₄O₄ and contains a methoxyl group. It has also a phenolic or enolic hydroxyl group. Demethylation with aluminium chloride yields nor-pongamol whereas treatment with hydriodic acid gives rise to a product which is probably isomeric but does not possess phenolic properties. Treatment with bromine produces a tetrabromo derivative which on boiling with acetone yields a tribromo compound. Oxidation with potassium permanganate or decomposition with alkali yields benzoic acid. From these properties and from colour reactions it is suggested that pongamol is a flavone derivative containing a hydroxyl, a methoxyl and an ethylene double bond.