Spirodienones. Part 5. The synthesis and reactions of N-sulphonylcyclohexadienimines

Abstract

The anodic or chemical oxidation of para-substituted sulphonanilides gives 4,4-disubstituted N-sulphonylcyclohexadienimines, which, from appropriately substituted anilines, may be spirocyclic. The scope and limitations of the synthesis are described, and a mechanism proposed. The selective hydrolysis of the dienimines to the corresponding dienones provides a convenient route to the latter compounds. The reaction of some of the dienimines with dienes is discussed.