Is the 2,3-carbon-carbon bond of indole really inert to oxidative cleavage by Oxone?--synthesis of isatoic anhydrides from indoles.

A recent report has indicated that the oxidizing agent Oxone does not possess the ability to cleave the 2,3-carbon-carbon bond of indole. Work in our laboratory shows that this is not the case. Indole and a variety of aryl ring substituted derivatives readily react to form synthetically important isatoic anhydrides.