Conjugated dienes are a class of click chemistry reagents containing two double bonds separated by a single bond. They are more stable than non-conjugated or cumulated dienes, which have the double bonds separated by more than one single bond or connected to the same atom, respectively. Conjugated dienes can react with dienophiles to form substituted cyclohexene derivatives via the Diels-Alder (DA) click reaction. https://www.alfa-chemistry.com/click-chem/conjugated-dienes.html