Cycloaddition reactions of cyclic and acyclic 1,3-dipoles with diphenylcyclopropenone and related compounds. A new rearrangement

Abstract

Cycloaddition of mesoionic compounds with diphenylcyclopropen-one and -thione, and tosylimino- and dicyanomethylene-cyclopropene occurs across the endocyclic CC double bond, whereas cycloaddition of benzonitrile oxide with diphenylcyclopropenone occurs across the CO double bond to give triphenyl-1,3-oxazin-6-one by a new type of rearrangement.