Hexamethylbenzene (1) reacts with dimethyldioxirane (2) via three separate reaction pathways. In the major pathway the reaction proceeds through an arene oxide which is rapidly transformed to the oxepin valence tautomer. In the first example of the reaction of an oxepin with 2 the oxepin is oxidized to first the cis-dioxide and then to the trioxide with the third oxide trans to the other two oxide rings. In a second competing pathway a methyl ...
