Earth-Abundant Recyclable Magnetic Iron Oxide Nanoparticles for Green-light Mediated C-H Arylation in Heterogeneous Phase.

A magnetically isolable iron oxide nanoparticles is introduced as an efficient heterogeneous photocatalyst for non-directed C-H arylation employing aryl diazonium salts as the aryl precursors. This first-row transition metal-based photocatalyst revealed versatile activities and is applicable to a wide range of substrates, demonstrating brilliant efficacy and superior recyclability. Detailed catalytic characterization describes the physical properties and redox behavior of the Fe-catalyst. Adequate control experiments helped to establish the radical-based mechanism for the C-H arylation.

An organophotoredox-catalyzed redox-neutral cascade involving N-(acyloxy)phthalimides and allenamides: synthesis of indoles.

An organophotoredox-catalyzed radical cascade of allenamides and alkyl N-(acyloxy)phthalimides for the synthesis of indoles is documented. The method features mild and robust reaction conditions, and exhibits broad scope. The tandem process enriches the limited repertoire of alkyl NHPI ester addition on electron-rich π-bonds as well as radical chemistry involving allenamides.