Iodine-Catalyzed C-N Bond Formation: Synthesis of 3-Aminoquinoxalinones under Ambient Conditions.

Abstract

A metal-free cross-dehydrogenative coupling between quinoxalinones (sp2 C-H) and amines (N-H) in the presence of catalytic iodine is reported. The reaction yields 3-aminoquinoxalinones in moderate to high yields under ambient conditions in dioxane as solvent and aqueous tert-butyl hydroperoxide (TBHP) as the terminal oxidant. The reaction is highly versatile and exhibits good functional group tolerance with a range of primary and secondary amines. It provides a practical access to pharmaceutically active 3-aminoquinoxalinone derivatives. Preliminary mechanistic studies reveal in situ iodination of the amine as the putative mode of activation.