Electrochemical oxidations of 1,3-dihydro-1,3-diaza-azulanones and effects of reaction temperature

Electrochemical oxidations of 1-tosyl-3-aryl-1,3-dihydro-1,3-diazaazulanones at 0 degreesC afforded 3-aryl-6-tosyl-1,3-dihydro-1,3-diazaazulanones via migrations of the tosyl group. However, the same type of electrochemical oxidations at an elevated temperature (25 C) gave another type of product, i.e., double bond isomers, 1-tosyl-3-aryl-1,3-dihydro-1,3-diazaazulanones via 1,5-hydrogen migration, together with 3-aryl-6-tosyl-1,3-dihydro-1,3-diazaazulanones.