Abstract (1 Z,3 Z)-Butyltelluro-4-methoxy-1,3-butadiene 2 was obtained by the hydrotelluration of ( Z)-1-methoxy-but-1-en-3-ynes 1. The butadienyllithium 3 obtained by the Te/Li exchange reaction in the (1 Z,3 Z)-1-butyltelluro-4-methoxy-1,3-butadiene 2 reacted with aldehydes to form the corresponding alcohols 4a– d with total retention of configuration. The alcohols formed undergo hydrolysis, resulting in the α,β,γ,δ-unsaturated aldehydes of ( E, E) configuration, which are precursors of trienes obtained from natural sources. The products of this reaction were employed in the synthesis of methyl-(2 E,4 E)-decadienoate 7, which is a component of the flavor principles of ripe Bartlett pears. Performing the Wittig reaction of the methyl triphenylphosphorane with the deca-(2 E,4 E)-dienal 5a, we were able to synthesize the undeca-(1,3 E,5 E)-triene 6a. This compound is a sex-pheromone component of the marine brown algae Fucus serratus, Dictyopteris plagiograma, and Dictyopteris australis. Performing the Wittig reaction of methyl triphenylphosphorane with the octa-(2 E,4 E)-dienal 5c, the nona-(1,3 E,5 E)-triene 6b was synthesized. The compound obtained is a sex-pheromone component of the marine brown alga Sargassum horneri. The octa-( 1, 3E, 5E)-triene 6c was easily obtained from hepta-(2 E,4 E)-dienal 5d by the Wittig reaction with methyl triphenylphophorane. This compound is a sex-pheromone component of the marine brown alga Fucus serratus.