Studies on radical-mediated site-selective C–H functionalizations of heteroarenes

Abstract

The powerful methods of site selective C C bond formation have been developed. Site selective C C bond formation require external oxidant, harsh condition. In first work, carbon radical is generated by 1,5 hydrogen atom transfer of N Centered radical, produced γ pyridyl carboxamides and δ pyridyl sulfonamides. In second work, beta scission of cycloalkoxy radical without prefunctionalization. Interestingly, carbon radicals are C4 selectively added to pyridinium salt in these protocols. In addition, these methods can generate not only amide, ketone but also aldehyde and ester compounds. These novel synthetic tools are eco friendly mild reaction condition, wide substrate scope and bond formation selectivity.