Abstract: The photochemistry of the vinyl substituted (E)-3-(anthran-9-yl)propenoates and (E)-9-(aroylethenyl)anthracenes as well of their reduced derivatives has been studied at lambda = 254 nm and at lambda= 352 nm. At lambda = 254 nm and lambda= 352 nm, the 9-vinyl substituted anthracenes undergo E/Z-isomerization, while their reduced derivatives undergo [4+4]-dimerisation reactions at lamda = 352 nm. An X-ray crystal structure shows the [4+4]-photoadducts to be head-to-tail. The photochemistry of cycloadducts of (E)-3-(anthran-9-yl)propenoates and (E)-9-(aroylethenyl)anthracenes with maleimides and other activated dienophiles show a number of reactions, among them retro-cleavage of the cycloadducts to the respective anthracenes.