Trisubstituted alkenes are crucial building blocks in pharmaceutical and materials science. Their stereoselective synthesis remains a significant challenge in organic chemistry. Current methods often produce only one stereoisomer or require pre-functionalized starting materials. This research explores multi-component reactions (MCRs) for one-pot alkyne difunctionalization, aiming for a more efficient and versatile synthesis of trisubstituted alkenes with control over both *E* and *Z* stereochemistry. Photocatalysis and electrochemistry, individually and in combination (dual catalysis), have emerged as powerful tools for organic synthesis, offering mild reaction conditions and unique reaction pathways. The authors hypothesize that by exploiting the electron transfer capabilities of electrochemistry and photocatalysis in conjunction with nickel catalysis, they can achieve stereodivergent synthesis of trisubstituted alkenes. Previous work by the authors showed successful stereocontrol in aryl sulfonylation cross-coupling, but the extension to alkylarylation was limited to *syn* addition due to energy transfer processes in photoredox/nickel dual catalysis. The current study aims to overcome this limitation using electrochemical methods to circumvent the energy transfer process.

The paper reviews existing methods for the stereoselective synthesis of trisubstituted alkenes, highlighting their limitations in achieving stereodivergence or requiring pre-functionalized substrates. It discusses the advantages of photocatalysis and electrochemistry, both independently and in dual catalytic systems, in achieving mild and efficient organic transformations. The authors' previous work on photoredox and nickel dual-catalyzed cascade reactions is mentioned, pointing out the limitation of achieving *anti*-selectivity in alkylarylations due to energy transfer processes. Various examples of dual catalysis using different metal catalysts with both photocatalysis and electrochemistry are cited.

The authors developed a three-component reductive cascade cross-coupling reaction using aryl bromides, alkynes, and alkyl bromides. They investigated three distinct catalytic pathways: (1) electrocatalytic nickel catalysis, (2) photoredox/nickel dual catalysis, and (3) a photo-assisted electrocatalytic approach. In the electrochemical method, a constant current of 4 mA was applied for 16 h using a graphite anode and a nickel foam cathode in DMA solvent. The photoredox/nickel dual catalysis employed a photocatalyst (Pc1), nickel bromide, and a combination of amines and LiCl in DMA under 440 nm blue LED irradiation. The photo-assisted electrochemical method combined electrochemical conditions with 390 nm purple LED irradiation without the addition of a photocatalyst. The reaction scope was explored for different aryl bromides, alkynes, and alkyl bromides, under all three catalytic pathways. Mechanistic studies were performed using radical trapping experiments and Stern-Volmer quenching experiments, coupled with cyclic voltammetry to investigate the reaction mechanism.

The electrochemical approach using nickel catalysis provided the *E*-isomer of the trisubstituted alkene exclusively, showcasing high stereoselectivity. A broad substrate scope was achieved, with various functional groups tolerated on aryl bromides and alkynes. The photoredox/nickel dual catalysis selectively generated the *Z*-isomer of trisubstituted alkenes with good stereoselectivity. A variety of electron-rich and electron-poor aryl halides, alkynes, and alkyl bromides were shown to be suitable substrates. The photo-assisted electrochemical approach, without the addition of a photocatalyst, also selectively delivered *Z*-trisubstituted alkenes with good to excellent stereoselectivity. Mechanistic investigations suggest that alkyl radicals are involved in the transformation, and the stereochemical outcome is controlled by the absence or presence of energy transfer during the process. Scale-up reactions were successfully performed, maintaining yield and stereoselectivity. The synthetic utility was demonstrated through the synthesis of a complex molecule featuring three natural-product-derived motifs (probenecid, estrone, and galactopyranose). Further functionalization of the trisubstituted alkene products was successful through fluorinative alkoxylation, electrochemical hydrogenation, photochemical trifluoromethylation, epoxidation, and vinyl C–H bromination.

This study successfully demonstrates a stereodivergent synthesis of trisubstituted alkenes by carefully controlling the reaction conditions. The ability to switch between *E* and *Z* selectivity simply by changing the reaction methodology (electrochemical vs. photocatalytic) or by utilizing photo-assisted electrochemistry highlights the power of combining electrochemistry and photocatalysis with nickel catalysis. The mechanistic studies provide a good understanding of the reaction pathways and the factors influencing stereoselectivity. The broad substrate scope and successful scale-up and further functionalization showcases the synthetic utility and practicality of this methodology. This method provides a significant advance in the synthesis of trisubstituted alkenes, which are prevalent in pharmaceuticals and materials.

This work presents a highly efficient and versatile three-component reductive cascade cross-coupling reaction for the stereodivergent synthesis of trisubstituted alkenes. The ability to control the stereochemistry by switching between electrocatalytic, photocatalytic, or photo-assisted electrocatalytic methods offers a powerful synthetic tool. The broad substrate scope and successful late-stage functionalization highlight the synthetic potential. Future research could explore further optimization of reaction conditions and the development of asymmetric variations.

While the methodology shows high stereoselectivity and a broad substrate scope, there are some limitations. Certain substrates provided moderate yields, and the mechanistic understanding is still under development, although the radical pathway is suggested by mechanistic studies. Further exploration of the mechanism and optimization of reaction conditions for specific substrates might improve the yields and expand the reaction scope.