The thermolysis of 0-, m-, and p-tolyldiazomethanes to styrene and benzocyclobutene poses a mechanism problem of substantial interest. Several intriguing solutions to this problem have been suggested, 14 and labeling st~ dies,',~*~ have placed severe mechanistic constraints on possible solutions. Our studies on the phenylmethylene-cycloheptatetraene interconver~ ion~ prompted an investigation of the tolylmethylene rearrangement. We now ...
