Synthesis of 7- and 8-Functionalized 2-Aminophenoxazinones via Cyclocondensation of 2-Aminophenols

An efficient protocol for the synthesis of 7- and 8-functionalized 4- and 2-amino-3 H -phenoxazin-3-ones and 2-amino-1 H -phenoxazin-1-ones by oxidation of 2-aminophenols using hydrogen peroxide activated by ebselen is presented. We demonstrate that formation of the 2-amino-3 H -phenoxazin-3-one core requires that the substituents present on one of the reacting substrate molecules be eliminated under oxidative reaction conditions.