The dehydrogenative alkenylation of C-H bonds with alkenes represents an atom-and stepeconomical approach for olefin synthesis and molecular editing. Site-selective alkenylation of alkanes and aldehydes with the C-H substrate as the limiting reagent holds significant synthetic value. We herein report a photocatalytic method for the direct alkenylation of alkanes and aldehydes with aryl alkenes in the absence of any external oxidant. A diverse range of commodity feedstocks and pharmaceutical compounds are smoothly alkenylated in useful yields with the C-H partner as the limiting reagent. The late-stage alkenylation of complex molecules occurs with high levels of site selectivity for sterically accessible and electron-rich C-H bonds. This strategy relies on the synergistic combination of direct hydrogen atom transfer photocatalysis with cobaloxime-mediated hydrogen-evolution cross-coupling, which promises to inspire additional perspectives for selective C-H functionalizations in a green manner.

Enantioenriched 1,4-dicarbonyl compounds are versatile synthons in natural product and pharmaceutical drug synthesis.W eh erein report am ild pathway for the efficient enantioselective synthesis of these compounds directly from aldehydes through synergistic cooperation between an eutral eosin Yh ydrogen atom transfer photocatalyst and ac hiral rhodium Lewis acid catalyst. This method is distinguished by its operational simplicity,a bundant feedstocks, atom economy,and ability to generate products in high yields (up to 99 %) and high enantioselectivity (up to 99 %ee).Scheme 1. Synthesis of 1,4-dicarbonyl compounds through asymmetric acyl radical conjugateaddition.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.Scheme 5. Gram-scale synthesis and further synthetic diversification.Scheme 6. Proposed reaction mechanism for the merged HATphotocatalysis and asymmetric Lewis acid catalysis. RHAT = reverse hydrogen atom transfer.

Deuterium labelled compounds are of significant importance in chemical mechanism investigations, mass spectrometric studies, diagnoses of drug metabolisms, and pharmaceutical discovery. Herein, we report an efficient hydrogen deuterium exchange reaction...

A visible-light-mediated radical Smiles rearrangement has been achieved using neutral eosin Y as a direct hydrogen atom transfer (HAT) photocatalyst. Novel N-heterocycles as single diastereomers featuring an isothiazolidin-3-one 1,1-dioxide moiety are directly accessed by this method. A wide range of functional groups can be incorporated in the products by employing diverse aldehydes and N-(hetero)­arylsulfonyl propiolamides. The transformation proceeds through a cascade of visible-light-induced HAT, 1,4-addition, Smiles rearrangement, 5-endo-trig cyclization, and a reverse HAT process. Preliminary biological studies of the highly functionalized heterocyclic compounds suggest potential anticancer activity with some of the synthesized compounds.

The rational design of high-performance catalysts is hindered by the lack of knowledge of the structures of active sites and the reaction pathways under reaction conditions, which can be ideally addressed by an in situ / operando characterization. Besides the experimental insights, a theoretical investigation that simulates reaction conditions—so-called operando modeling—is necessary for a plausible understanding of a working catalyst system at the atomic scale. However, there is still a huge gap between the current widely used computational model and the concept of operando modeling, which should be achieved through multiscale computational modeling. This Perspective describes various modeling approaches and machine learning techniques that step toward operando modeling, followed by selected experimental examples that present an operando understanding in the thermo- and electrocatalytic processes. At last, the remaining challenges in this area are outlined.

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As a new antioxidant, nanoceria is of significant importance in applications of medical and biological fields. In comparison with conventional organic antioxidants, nanoceria has multienzyme mimetic activity by Ce 4+ /Ce 3+ redox cycle. This unique regenerative/autocatalytic property has been widely used in the aspects of free-radical scavenger, radiation protection, oxidativestress-related disease, drug delivery, biosensor, tissue engineering, cancer biomarker, and anti-inflammatory. This paper reviews the latest breakthrough of nanoceria as an antioxidant in applications of medical and biological fields on the base of the authors' research works on resistance to oxidation and cytotoxicity. The challenges of nanoceria encountered in applications in medical and biological fields are commented as well.

While aldehydes represent a classic class of electrophilic synthons, the corresponding acyl radicals are inherently nucleophilic, which exhibits umpolung reactivity. Generation of acyl radicals typically requires noble metal catalysts or excess oxidants to be added. Herein, we report a convenient and green approach to access acyl radicals, capitalizing on neutral eosin Y-enabled hydrogen atom transfer (HAT) photocatalysis with aldehydes. The generated acyl radicals underwent SOMOphilic substitutions with various functionalized sulfones (X–SO2R’) to deliver value-added acyl products. The merger of eosin Y photocatalysis and sulfone-based SOMOphiles provides a versatile platform for a wide array of aldehydic C–H functionalizations, including fluoromethylthiolation, arylthiolation, alkynylation, alkenylation and azidation. The present protocol features green characteristics, such as being free of metals, harmful oxidants and additives; step-economic; redox-neutral; and amenable to scale-up assisted by continuous-flow technology.