| Summary: | Syntheses of (11<i>Z</i>,13<i>Z</i>)-hexadecadienal (<b>1</b>), (11<i>Z</i>,13<i>Z</i>)-hexadecadienol (<b>2</b>), (11<i>Z</i>,13<i>Z</i>)-hexadecadien-1-yl acetate (<b>3</b>), and (Z)-13-hexadecen-11-ynal (<b>4</b>) from commercially available starting material 10-bromo-1-decanol are reported. These (<i>Z</i>,<i>Z</i>)-dienes and conjugated en-yne moieties are common in sex pheromone and attractant components for many Notodontide insect pests. The synthetic scheme, using the C10 + C3 + C3 strategy, was mainly based on three key steps: alkylation of lithium alkyne under a low temperature, <i>cis</i>-Wittig olefination of the aldehyde with propylidentriphenylphosphorane, and hydroboration-protonolysis of alkyne. This synthetic route provided (11<i>Z</i>,13<i>Z</i>)-hexadecadienal (<b>1</b>) in a 23.0% total yield via an eight-step sequence, alcohol (<b>2</b>) in a 21.9% total yield, acetate (<b>3</b>) in a 21.4% total yield, and (Z)-13-hexadecen-11-ynal (<b>4</b>) in a 34.7% total yield. This simple strategy provides a new way to achieve syntheses of the key sex pheromones of Notodontide insect pests.
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