An Intramolecular Radical C–N Coupling by N-Iodosuccinimide

Abstract

This manuscript presents a useful method for the formation of benzimidazole-fused phenanthridines through an intramolecular coupling of unactivated C(sp2)-H and N(sp3)-H bonds using N-iodosuccinimide (NIS) in trifluoroethanol (TFE). The synthesis of benzo[4,5]imidazo[1,2-f]phenanthridines from 2-([1,1'-biphenyl]-2-yl)-1H-benzo[d]imidazole derivatives describes as mild, efficient, and sustainable, with high yields and minimal waste generation. The control experiments and EPR studies aimed at rationalizing the radical pathway of the reaction. Specifically, the use of 1,1-diphenylethylene, TEMPO, BHT, and DMPO as a free-radical spin-trapping reagent in EPR studies, allowed us to conceive a radical pathway. The gram-scale synthesis further supported the practical utility of the methodology for the field of synthetic chemistry.

Application of Bertagnini's Salts in a Mechanochemical Approach Toward Aza‐Heterocycles and Reductive Aminations via Imine Formation

“…The significance of benzimidazole and its analogues [17] (Figure 2) in the fields of natural products, [18] pharmaceutical, [19] and biological chemistry [20] highlights the importance of their synthesis. However, conventional methods [21] often require catalysts, oxidants, or high reaction temperatures.…”

Visible Light Induced Three‐Component 1,2‐Dicarbofunctionalization of Alkenes and Alkynes

“…Recently, the use of photo‐mediated functionalization has become increasingly popular due to its high level of sophistication, efficiency, and straightforwardness as a pathway for creating new chemical compounds [17] . It has gained popularity due to its simple operation and eco‐friendly energy sources [10a,18] . Therefore, the application of visible‐light in three‐component dicarbofunctionalization (Scheme 1) is unquestionably a decent choice in conventional synthetic wisdom.…”