Changing the odor properties of commercial mixtures of alpha -irones by simple chemical transformations

The sensory properties of commercial mixtures of alpha-irones were modified by means of simple chemical trans formations, enriching the original mixtures in their content of gamma-isomers. The sequence employed consisted of NaBH4 reduction, acetylation with Ac2O in pyridine, photoisomerization, saponification and MnO2, oxidation. New odor sensations can be elicited by manipulation of commercial odorants.