Green Synthesis, Formulation and Test Field of Lymantria monacha L. (Lepidoptera: Lymantriidae) Sex Pheromone in East European Region.

The nun moth, Lymantria monacha L. (Linnaeus, 1758), is one of the most important defoliators of coniferous forests in Europe and Asia. In sexual communication, females produce three epoxides and an alkene: (-)-disparlure [(7 S ,8 R )- cis -7,8-epoxy-2-methyloctadecane], (+)-monachalure [(7 R ,8 S )- cis -7,8-epoxyoctadecane], (-)-monachalure [(7 S ,8 R )- cis -7,8-epoxyoctadecane], and their corresponding olefins. This study aimed to develop a green synthesis pathway for all pheromonal components, emphasizing the use of common raw materials, a simplified three-step process, lower costs, and an environmentally friendly approach compared to existing methods. The proposed method introduces a novel synthetic route employing an innovative improvement alkylation step catalyzed by lithium iodide in diglyme. The synthesized compounds were characterized using GC-MS, ¹ H NMR, and ¹³ C NMR spectroscopy. Six synthetic blends were formulated for field testing, with the goal of identifying the most attractive composition. Field trials demonstrated that a blend with a 10:10:1 ratio of (±)-Disparlure, (±)-Monachalure, and ( Z )-2-Methyl-7-octadecene exhibited the highest attraction efficiency.