Regioselective C(sp2)-H nitrosation and nitration of (Hetero)arenes with Fe(NO3)3·9H2O as promoter, nitroso and nitro source

A regioselective C(sp²)-H nitrosation and nitration protocol has been successfully developed for the modification of various undirected bioactive molecules by using the economical and nontoxic Fe(NO₃)₃^.9H₂O as nitroso/nitro source. This method is conducted under acid-free and ease of handling conditions and is featured with good regioselectivity as well as a broad substrate scope (38 examples; yields up to 90 %). This reaction could be conducted on a gram scale with good efficiency, demonstrating high utility for the synthesis and modification of drug and material molecules. Detailed mechanistic studies indicate that the formation of the nitroso or nitro products might be proceeded via the radical cross coupling of aryl radical cation intermediates with nitroso or nitro radical.