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Updated: Apr 3, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Identification of a Grain Beetle Macrolide Pheromone and Its Synthesis by Ring-Closing Metathesis Using a Terminal
Susann Hötling1, Celine Bittner2, Matthias Tamm2
1Institut für Organische Chemie, Technische Universität Braunschweig , Hagenring 30, 38106 Braunschweig, Germany.
Abstract:
A major C18-macrolide was found during analysis of the frass of the storage beetle Oryzaephilus surinamensis to be (9Z,12Z,15R)-octadeca-9,12-dien-15-olide (10, cucujolide XI). The synthesis used ring-closing alkyne metathesis as a key step. The highly active 2,4,6-trimethylbenzylidyne molybdenum complex [MesCMo{OC(CF3)2Me}3] (12) allowed the use of a terminal alkyne and afforded the product in excellent yield. Bioassays proved the activity of the R-enantiomer 10 in the aggregation of the beetle. Cucujolide XI is the first macrolide pheromone oxidized at the ω-4 position.
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