Radical Cyclization/Fragmentation Reactions of Dicyanocyclopropanes to Enaminonitriles. A Radical Alternative to the Thorpe-Ziegler Reaction

Radical cyclizations to dicyanocyclopropanes provide\ud cyclic enaminonitriles by a series of radical reactions that features radical cyclization to a nitrile and cyclopropane cleavage. The direction of cyclopropane cleavage—and hence the ring size of the final product—depends on the nature of the ring formed in the initial cyclization to the nitrile