Transition Metal-Free Heteroarylation of Quinoxaline: Construction of Heteroaryl-Fused Phenazines by Oxidative Coupling

Abstract

O-mediated oxidative coupling of di-heteroarylated quinoxalines for the first time. Synthesis of mono- and di-heteroarylation of quinoxaline was performed effectively using only LiTMP reagent under transition metal-free conditions and without the use of halogen-containing starting compounds. In addition, nonsymmetrical di-heteroarylated quinoxalines were synthesized through reheteroarylation of mono-heteroarylated quinoxalines in the same way. Oxidation of the saturated compounds formed after heteroarylation was easily accomplished with iodine. The UV-vis absorption and fluorescence features of some compounds were examined.