Chiral monoterpenes 3-carene

From the investigated chiral monoterpenes 3-carene has been detected in only (+)-form. p-pinene and P-phellandrene has been identified as (-)-P-pinene and (+)-P-phellandrene of a high enantiomeric purity. A small amount of their optical antipodes has also been detected in some samples. 

In the past year, (+)- a -crysanthemic acid has been prepared from a number of readily available chiral monoterpenes, namely (—)-carvone, (+)-limonene, a-terpineol, and (+)-3-carene. Furthermore, an asymmetric synthesis of (liJ)-cw-permethric acid (11) has been achieved by the reaction of 1-menthyl diazoacetate and l,l-dichloro-5-methylpenta-l,3-diene in the presence of the... 

ISO standard 3215 shows character and data for this oil. Adulteration is done by monoterpenes a- and P-pinene, sabinene from different sources, and a- and p-phellandrene as well as synthetic linalool, terpinen-4-ol and a-terpineol. In the past, safrole from sassafras oil was used for blending. Detection is done by GC-MS, looking for the quantities of safrole and myristicin in addition 2D chiral separation is recommended. Konig et al. (1992) reported the following chiral ratios (+)-a-thujene 10.3% (-) a-thujene 89.7% (-)-a-pinene 79.3 (+)-a-pinene 20.7% (-)-camphene 100% (+)-camphene 0% (+)-P pinene 41.9% (-) p-pinene 58.1% (-)-a-phellandrene 0% (+)-a-phellandrene 100% (+)-sabi-nene 89.5% (-)-sabinene 10.5% (+)-5-3-carene 0% (-)-5(-)-3-carene 100% (-)-p-phellandrene 7.7% (+) p-phellandrene 92.3% and (-)-limonene 60.9% (+)-limonene 39.1%. 

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