Social behavior of insects always fascinates human beings as they appear to maintain good order and communication in the society. Insects have developed sophisticated chemical communication systems using their pheromones for the purpose. Among the pheromones, cuticular wax is used to recognize group members from non-members. In ants, there have been identified close to 1,000 cuticular hydrocarbons (CHCs) and the composition of CHCs of cuticles works for the discrimination between their friends and foes. Some species of ants are known to use cuticular wax of the dead ants in other colonies to disguise their identity when they invade other colonies. It was known that the antennae of ants recognize the composition of the CHCs but the exact mechanism of this recognition has not been well studied. The CHCs on the cuticles are also used to distinguish the queen ant from other fertile ants. Queen ants produce 3,11dimethylated linear hydrocarbons longer than C26 (Figure 1). Interestingly, only the odd numbered carbon chains ranging from 27 to 33 are found in insect society. These CHCs are also coated on the eggs of the queen but do not exist on those of other ants, which allow ants to distinguish those eggs and destroy the latter by eating to control their social hierarchy. We became interested in the recognition mechanism of the different composition of CHCs and the effect of the disruption of CHC composition on the social behavior of ants. For these studies, we need to devise a versatile synthetic route to these branched hydrocarbons. Herein, we report the first synthesis of 3,11-dimethylheptacosane (1) through a short and versatile synthetic route. The synthetic analysis of 3,11-dimethylheptacosane (1) shows that intermolecular enyne metathesis can allow to introduce two methyl group on the chain and the overall chain length could be controlled by using an alkyne with proper chain length (Scheme 1). Two methyl groups of 1 can be obtained from two conjugated dienes of 2. These two diene fragments, 3 and 4, can be prepared through enyne metathesis of tosylated butynol 6 with proper olefin. This synthesis would not require any protecting group and allows that alkyne 5 could be replaced by other alkynes with different chain length for the synthesis of all possible CHC pheromones. The synthesis started from 3-butynol to produce the corresponding tosylate 6. The alkyne 6 was treated with the second generation Grubbs catalyst (Grubbs II) under ethylene atmosphere to produce diene 3. Since allyl bromide was not