The first example for the diene-transmissive Diels-Alder reaction of 2
-vinyl-1-oxabutadiene system is presented by the reactions of 1,5-diph
enyl- and 1,5-di(2-thienyl)-1,4-pentadien-3-ones with electron-rich en
amines as the first dienophiles and then with electron-deficient dieno
philes as the second.