Large quantities of carbocyclic helicenes, for example 1, can be made by a new procedure that combines divinyl aromatics with p-benzoquin0ne. l The key to good yields is to substitute alkoxy substituents at the a-positions of the styrenesa2 Although the Diels-Alder reactions of styrenes with p-benzoquinone and other dienophiles have been extensively studied: no similar transformations have been reported for the simplest examples, enol ...
