Synthesis of 9-geranylterpinolene as a mixture of isomers, and synthesis of α- and β-springene, possible kairomones of the beech leaf-mining weevil, Orchestes fagi (L.)

Abstract

The beech leaf-mining weevil, Orchestes fagi (L.), also known as the beech flea weevil, is a common and widespread pest of beech, Fagus sylvatica L., in its native Europe. It now appears to be well established in Nova Scotia, Canada. We have previously reported the synthesis of 9-geranyl-p-cymene and 9-geranyl-α-terpinene, as they are both found in eclosing beech buds, and have researched the synthesis of other diterpenes that are isomers of 9-geranyl-α-terpinene. We now wish to report a synthesis of the diterpene 9-geranylterpinolene as a mixture of isomers, as a novel diterpene, and as a possible kairomone of O. fagi. Also, all trans-α-springene, its 3Z-isomer, and β-springene were synthesized as a mixture, as well as pure β-springene, utilizing known methods.

Graphical Abstract

Keywords:

• Beech leaf-mining weevil
• 9-geranylterpinolene
• kairomones
• α-springene
• β-springene

Acknowledgments

We thank Natural Resources Canada for funding this research. This research was partially supported by the Atlantic Canada Opportunities Agency, Atlantic Innovation Fund (No. 208171). All experiments reported here comply with the laws of Canada.

Disclosure statement

No potential conflict of interest was reported by the authors.