Visible‐Light‐Assisted Synthesis of Allylic Triflamides via Dual Acridinium/Co Catalysis

Electrochemical Synthesis of Itaconic Acid Derivatives via Chemodivergent Single and Double Carboxylation of Allenes with CO2

Leveraging electrochemistry, a new synthesis of non-natural derivatives of itaconic acid is proposed by utilizing carbon dioxide (CO2) as a valuable C1 synthon. An electrochemical cross-electrophile coupling between allenoates and CO2 was targeted, allowing for the synthesis of both mono- and di-carboxylation products in a catalyst- and additive-free environment (yields up to 87 %, 30 examples). Elaboration of the model mono-carboxylation product, and detailed cyclovoltammetric, as well as mechanistic analyses complete the present investigation.

Biomimetic Photoexcited Cobaloxime Catalysis in Organic Synthesis

Drawing inspiration from nature has long been a cornerstone of chemical innovation, with natural systems offering a wealth of untapped potential for discovery. In this minireview, we delve into the burgeoning field of cobaloxime catalysis in organic synthesis, which mimics the catalytic activity of the natural organometallic alkylcobalamine enzymes. Our focus lies on elucidating the latest advancements in this area, as well as delineating the primary mechanistic pathways at play. By describing, and comparing these mechanisms, we provide a comprehensive overview of the current state-of-the-art, while also shedding light on the key unresolved challenges that await further exploration.

Reductive cyclodimerization of chalcones: exploring the "self-adaptability" of galvanostatic electrosynthesis

The "self-adaptability" of galvanostatic electrolysis was shown to assist a multistage unprecedented chemo- and diastereoselective electrochemically promoted cyclodimerization of chalcones. The process, all involving the reductive events, delivered densely functionalized cyclopentanes featuring five contiguous stereocenters (25 examples, yields of up to 95%, dr values up to >20 : 1). Dedicated and combined experimental as well as electrochemical investigation revealed the key role of a dynamic kinetic resolution of the aldol intermediate for the reaction mechanism.

Electrochemical C(sp3)-H functionalization of ethers via hydrogen-atom transfer by means of cathodic reduction

The chemo- and stereoselective electrochemical allylation/alkylation of ethers is presented via a C(sp³)-H activation event. The electrosynthetic protocol enables the realization of a large library of functionalized ethers (35 examples) in high yields (up to 84%) via cathodic activation of a new type of redox-active carbonate (RAC), capable of triggering HAT (Hydrogen-Atom-Transfer) events through the generation of electrophilic oxy radicals. The process displayed high functional group tolerance and mild reaction conditions. A mechanistic elucidation via voltammetric analysis completes the study.

Regio- and Stereoselective Electrochemical Alkylation of Morita-Baylis-Hillman Adducts

Electrosynthesis is effectively employed in a general regio- and stereoselective alkylation of Morita-Baylis-Hillman compounds. The exposition of N-acyloxyphthalimides (redox-active esters) to galvanostatic electroreductive conditions, following the sacrificial-anode strategy, is proved an efficient and practical method to access densely functionalized cinnamate and oxindole derivatives. High yields (up to 80%) and wide functional group tolerance characterized the methodology. A tentative mechanistic sketch is proposed based on dedicated control experiments.

Visible-Light Assisted Covalent Surface Functionalization of Reduced Graphene Oxide Nanosheets with Arylazo Sulfones

We present an environmentally benign methodology for the covalent functionalization (arylation) of reduced graphene oxide (rGO) nanosheets with arylazo sulfones. A variety of tagged aryl units were conveniently accommodated at the rGO surface via visible-light irradiation of suspensions of carbon nanostructured materials in aqueous media. Mild reaction conditions, absence of photosensitizers, functional group tolerance and high atomic fractions (XPS analysis) represent some of the salient features characterizing the present methodology. Control experiments for the mechanistic elucidation (Raman analysis) and chemical nanomanipulation of the tagged rGO surfaces are also reported.