Queen bee substance

This reaction provides a useful way of introducing a double bond next to a carbonyl group. Here it is in a synthesis by Barry Trost of the Queen Bee Substance (the compound fed by the workers to those bee larvae destined to become queens). The compound is also a pheromone of the termite and is used to trap these destructive pests. Trost started with the monoester of a dicarboxylic acid, which he converted to a methyl ketone by reacting the acyl chloride with a cuprate. The ketone was then protected as a dioxolane derivative to prevent it enolizing, and the sulfur was introduced by reacting the enolate of the ester with the sulfur electrophile MeSSMe. 

Next, the protecting group was removed with acid, and the sulfide was oxidized to the sulfoxide with sodium periodate (NaI04) ready for elimination. Heating to 110°C then gave the Queen Bee Substance in 86% yield. 

Based on this method, simple and efficient syntheses of prmtaglandin intomediates, Queen bee substance, zearalenone, dihydtojasmone, jasmone, diplodialide B, lasiodiplodin methyl ether, ... 

Dicarboxylic esters are used to prepare polyesters and polyamides. The residual double bonds permit cross-linking of the polymer chains. Cross metathesis of methyl oleate with excess ethene affords methyl 9-decenoate, a key intermediate in the synthesis of queen bee substance , a honey bee pheromone. 

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