Photoredox‐Initiated α‐Alkylation of Imines through a Three‐Component Radical/Cationic Reaction

Direct CH Functionalization of Enamides and Enecarbamates by Using Visible‐Light Photoredox Catalysis

“…[16c] Courant and Masson demonstrated the generation of b-alkylated a-amido ethers from N-acyliminium cations that were derived from enecarbamate-based SOMOphiles. [13] To the best of our knowledge, there are no reported examples on the preparation of functionalized enamides through visiblelight photoredox catalysis. Herein, we would like to report our efforts in direct CÀH functionalization of enamides or enecarbamates mediated by visible-light photoredox catalysis using enamides as SOMOphiles.…”

“…[1,9] With our continuing efforts to use photoreactions as atom-economic synthetic approaches to various frameworks, [10] we are interested in developing green and efficient synthetic approaches to functionalized enamides by direct C À H functionalization of enamides through SOMOphilic pathways. [11][12] Inspired by the recent work of Masson on the generation of b-alkylated a-amido ethers from N-acyliminium cations, which were derived from enecarbamate-based SOMOphiles (Figure 1), [13] we envisaged that N-acyliminium II, generated upon visible-light catalysis, might be able to tautomerize and give a functionalized enamide with the absence of nucleophiles in the reaction system. The incorporation into the reaction of the generation of the primary radical and the oxidation of the amido radical in the same visiAbstract: Direct CÀH functionalization of various enamides and enecarbamates was realized through visible-light photoredox catalyzed reactions.…”

Light on Unsaturated Hydrocarbons – “Gotta Heterofunctionalize Them All”

“…[64] They envisaged that the work of the Friestad group on the tin-mediated radical alkylation of tertiary enamides [65] could be adapted in the presence of a nucleophile to yield the desired products upon visible-light catalysis. Thus, they proposed a second pathway that takes this into consideration (Path B).…”

Photopolymerization Reactions: On the Way to a Green and Sustainable Chemistry

“…The current efforts result in an amazing series of proposals of new PISs . For example, we have recently introduced PISs ( [99][100][101][102][103][104][105][106][107]) exhibiting really novel absorption properties (red-shift absorptions, multicolor absorptions, enhanced molar extinction coefficients, ε): e.g., colored substituted or functionalized ketones [60], modified organometallic derivatives [70][71][72][108][109][110][111][112][113][114][115][116][117] (ruthenium-, iridium-, platinum-, zirconium-and zinc-based complexes, titanocene derivatives…), various series of dye-based skeletons [61][62][63][65][66][67][68][74][75][76] (e.g., phenylenediamine, polystilbene, polyazine, violanthrone, acridinedione, 2,7-di-tert-butyldimethyldihydropyrene, bodipy, boranyl, thiophene, perylene bis-dicarboximide, hydrocarbons, pyrromethene, pyridinium salt…), di-and tri-functional architectures of photo initiators [64], light harvesting compounds [57,58] (where a strong molecular orbital coupling occurs, leading to ε huge values) and push-pull and multicolor photoinitiators (novel chromophores; donor--acceptor arrangements; unusual broad absorptions from the blue to the red wavelengths…).…”

“…The further introduction of the silyl chemistry into photoredox cycles (as those known in organic synthesis purposes using photocatalysts (PC) [108][109][110][111][112][113][114][115][116][117]) has recently led to interesting possibilities of FRP and FRPCP reactions under soft conditions in aerated media [75,76,[105][106][107]. Novel PIs working as PCs through an oxidation cycle (metal complexes or organic metal-free compounds) in combination with a silane and an iodonium salt have been designed (22)(23)(24)(25); they allow successful excitations of cationic or radical matrices up to 635 nm under air.…”