Palladium-catalyzed cycloisomerisation reaction of 1, 6-enyne acetic esters to form five-membered nitrogenated heterocyclic conjugated trienes

•Importance of five-membered nitrogenated heterocyclics as pharmaceutical and bioactive agents.•A one-pot to construct five-membered nitrogenated heterocyclics bearing conjugated trienes motif.•The reactions show excellent regioselectivity, good functional group tolerance and high yields.•The resulting conjugated trienes could be facilely converted to highly substituted benzenes through Diels-Alder reactions.