Vinyl pentanoate ($\mathrm{C}{\mathrm{H}}_2=\mathrm{CHOC}(\mathrm{O})(\mathrm{C}{\mathrm{H}}_2{)}_3\mathrm{C}{\mathrm{H}}_3$)

Vinyl pentanoate is the ester $\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{C}(=\mathrm{O})\mathrm{OCH}=\mathrm{C}{\mathrm{H}}_2$. Its pentanoyl portion and its vinyl portion provide chemically distinct sites for reaction.

During acyl transfer, release of vinyl alcohol can be followed by conversion to acetaldehyde. Coupling these transformations can favour transfer of the acyl group, illustrating how a product's subsequent reaction changes an overall equilibrium.