Many odoriferous compounds, particularly those isolated from plants, are optically active due to the presence of at least one chiral center in their molecular structure. Optical isomers, or enantiomers, sometimes exhibit different biological and olfactory properties. Therefore, chemists seek to develop simple methods for the preparation of such components and this can be a challenging task. Moreover, data concerning the sensory and biological activity is more meaningful when dealing with a homochiral material than when dealing with a racemic mixture.
There are several approaches to the preparation of optically active compounds. One of these is to start with chiral starting materials, or chirons, isolated from plants.
This article presents the results of our recent work on the synthesis of novel, optically active odor compounds from chirons isolated from some plant materials. The chirons used were as follows: (+)-limonene, (+)-α-pinene, (+)-3-carene, (+)-longifolene and (+)-ricinoleic acid (Figure 1).