The importance of the 5-alkyl substituent for the violet smell of ionones: Synthesis of racemic 5-demethyl-α-ionone

Abstract

The synthesis and the odor tonalities of racemic 5-demethyl-α-ionone are described. This synthetic ionone derivative did not show the typical floral-woody violet smell of α-ionone, definitely proving the importance of a suitably sized and spatially oriented alkyl substituent at C(5) for stimulating olfactory receptors of ionones.