Pheromones offer a highly promising, biosphere-friendly approach to protect various crops. Unlike chemical pesticides, pheromones target only specific pest species, leaving other insects, especially pollinators (bees and wasps), unharmed. Additionally, pheromones are biodegradable, are used in small amounts, and therefore do not pose a threat to human health, making them ideal for modern, environmentally conscious farming. However, their synthesis shall be possibly straightforward and fully stereoselective, as the biological action of pheromones is often related to their E/Z-geometrical constitution. Therefore, as a final test for usefulness of our newly developed dithioquinoxaline-based catalyst we opted to prepare some well-known pheromones using Z-selective metathesis with Ru3. First, we approached synthesis of a precursor of sex pheromones of fall armyworm (Spodoptera frugiperda) oriental tobacco budworm moth (Helicoverpa assulta), corn earworm (Helicoverpa zea) and similar insects from the Noctuidae family that consume a wide variety of crops such as corn, tomato, pepper, rice, peanuts, and more. In a published method the CM reaction of methyl oleate (34) was conducted with 1-hexene and the second generation Hoveyda-Grubbs catalyst supported on silica. This transformation produced a rather complex mixture of products, including 1-decene, 5-tetradecene, methyl 9-decenoate and methyl 9-tetradecenoate (40). Obviously, due to application of non Z-selective catalyst this method suffered from very low E/Z-selectivity.