A general and practical method for the direct C–H amination of 2H-indazoles with a series of amines including aliphatic primary amines, secondary amines, azoles, and sulfoximines via organophotoredox-catalyzed oxidative coupling has been disclosed at room temperature under ambient air conditions. Additionally, this protocol is used for free aminated 2H-indazole synthesis. A mechanistic study revealed that a single electron transfer (SET) pathway might be involved in this reaction.

A mild, efficient, and one-pot protocol for three-component carbosilylation of alkenes with imidazoheterocycle and silanes has been developed by merging iron­(II) and visible-light photocatalysis. This C–C and C–Si bond-forming method provides functionalized organosilicon derivatives having imidazoheterocycles moieties in good yields. The reaction possibly proceeds through a radical pathway.

Switchable Rh(iii)-catalyzed highly regioselective hydroarylation and oxidative arylation of maleimides with 2-arylindazoles via C–H activation have been demonstrated.

Oxosulfonylation is a difunctionalization protocol where oxo and sulfonyl groups are introduced in one step to construct ketosulfones and Nacylsulfonamides from simple and readily accessible reagents. The development of oxosulfonylation methods has gained significant attention due to their importance in organic and medicinal chemistry. This review article provides a brief and concise overview of the current status and latest methodologies using green oxidant and sulfonyl sources for oxosulfonylation reactions developed in the last two decades.

A three-component vicinal carbophosphorothiolation of vinyl arenes by the cooperation of visible light and iron(II) catalysis has been established for the synthesis of S-alkyl phosphorothioates. Noteworthy, the late-stage functionalization of biologically active compounds has been performed using this procedure. The preliminary mechanistic study reveals that the catalytic cycle is accomplished by single-electron transfer (SET).