Herein, we report a hydrodefluorination reaction of polyfluoroarenes catalyzed by bismuthinidenes, Phebox-Bi(I) and OMe-Phebox-Bi(I). Mechanistic studies on the elementary steps support a Bi(I)/Bi(III) redox cycle that comprises C(sp 2 )–F oxidative addition, F/H ligand metathesis, and C(sp 2 )–H reductive elimination. Isolation and characterization of a cationic Phebox-Bi(III)(4-tetrafluoropyridyl) triflate manifests the feasible oxidative addition of Phebox-Bi(I) into the C(sp 2 )–F bond. Spectroscopic evidence was provided for the formation of a transient Phebox-Bi(III)(4-tetrafluoropyridyl) hydride during catalysis, which decomposes at low temperature to afford the corresponding C(sp 2 )–H bond while regenerating the propagating Phebox-Bi(I). This protocol represents a distinct catalytic example where a main-group center performs three elementary organometallic steps in a low-valent redox manifold.

The redox‐neutral dicarbofunctionalization of tri‐ and tetrasubstituted olefins to form a variety of (hetero)cyclic compounds under photoinduced palladium catalysis is described. This cascade reaction process was used to couple styrenes or acryl amides with a broad range of highly decorated olefins tethered to aryl or alkyl bromides (>50 examples). This procedure enables one or two contiguous all‐carbon quaternary centers to be formed in a single step. The products could be readily diversified and applied in the synthesis of a bioactive oxindole analogue.

No abstract

Die redoxneutrale Dicarbofunktionalisierung tri‐ und tetrasubstituierter Olefine zur Bildung verschiedener (hetero‐)cyclischer Verbindungen unter photoinduzierter Palladiumkatalyse wird beschrieben. Diese Kaskadenreaktion wurde verwendet, um zahlreiche an Aryl‐ oder Alkylbromide gebundene hochdekorierte Olefine mit Styrolen oder Acrylamiden zu kuppeln (>50 Beispiele). Durch dieses Protokoll können ein oder zwei zusammenhängende quartäre Kohlenstoffzentren in einem einzigen Schritt gebildet werden. Die Produkte ließen sich leicht diversifizieren und zur Synthese eines Analogons von bioaktiven Oxindolen verwenden.

Kavthe et al. (Chem. Sci., 2023, https://doi.org/10.1039/D3SC01699D) have demonstrated how employing more sustainable methodology can vastly reduce the environmental impact associated with the synthesis of the antimalarial drug candidate MMV688533.