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In this study, we have developed a metal-free, photoinduced energy transfer strategy for the efficient difunctionalization of carbon-nitrogen double bonds (C═N). Utilizing oxime ester-based bifunctional reagents, we have achieved direct radical difunctionalization of C═N bonds through nitrogen-nitrogen radical coupling, with over 35 examples and yields up to 96%. This method exhibits broad substrate scope, being compatible with a variety of carboxylic acids and biologically active molecules, thus offering a novel approach for the difunctionalization of heteroatom-containing unsaturated bonds in synthetic chemistry.

Utilizing energy transfer catalysis, this research employed the bifunctional reagents benzotriazole carboxylic acid oxime esters to simultaneously generate benzotriazole and imine radicals. The synthesis of two distinct C-N bonds in a single conversion is showcased through radical addition and radical-radical cross-coupling processes between benzotriazole carboxylic acid oxime ester and olefins. This process facilitates the intermolecular two-component unsymmetrical diamination reaction of olefins. Using this approach, more than 40 benzotriazole-containing molecules were successfully synthesized using styrene, indole, and benzofuran as acceptors, with yields ranging from moderate to excellent.

The 1,2-iminylalkylation of diazenes using alkyl iodides in combination with an O -benzoyl oxime is reported. In this transformation, O -benzoyl oxime acted as a radical precursor and XAT mediator. In addition to common alkyl iodides, other alkyl iodides such as iodomethane, iodomethane- d 3 , trifluoroiodomethane, ethyl difluoroiodoacetate, and iodoalkanes containing unprotected hydroxyl and amide groups can also serve as C-radical precursors in the 1,2-iminylalkylation with electrophilic diazenes as radical acceptors.

In this study, a metal-free difunctionalization strategy for diazenes was developed using a range of bifunctionalization reagents. This strategy involves a unique N(sp 3 )-N(sp 2 ) radical coupling between the hydrazine radical and the imine radical. More than 30 triazane core motifs were constructed by installing imines and various functional groups, including alkyl, phenyl, cyanoalkyl, and sulfonyl groups, on both ends of the nitrogen-nitrogen bond of diazenes in an efficient manner.

In this study, we developed a strategy using commercially available alkyl iodides and O -benzoyl oxime to efficiently introduce alkyl and iminyl groups via energy transfer and halogen-atom transfer processes. We performed three-component 1,2-carboimination of olefins and four-component 1,4-carboimination across olefins and alkynes, resulting in the synthesis of over 60 nitrogen-containing molecules. Moreover, this transformation enables the synthesis of molecules with sensitive groups that were previously difficult to achieve.

Imidazolinones were obtained in good yields by intramolecular hydroamination of N -alkoxy ureas in the presence of an organic photocatalyst and an inorganic base. In this reaction, the N -alkoxy urea anion generated by deprotonation undergoes photocatalyzed single-electron-transfer oxidation to generate the corresponding radical, which cyclizes to afford the imidazolinone ring. This new protocol grants access to an array of complex molecules containing a privileged imidazolinone core.

CO poisoning of Pt-group metal catalysts is a long-standing problem, particularly for hydrogen oxidation reaction in proton exchange membrane fuel cells. Here, we report a catalyst of Ru oxide-coated Ru supported on TiO 2 (Ru@RuO 2 /TiO 2 ), which can tolerate 1-3% CO, enhanced by about 2 orders of magnitude over the classic PtRu/C catalyst, for hydrogen electrooxidation in a rotating disk electrode test. This catalyst can work stably in 1% CO/H 2 for 50 h. About 20% of active sites can survive even in a pure CO environment. The high CO tolerance is not via a traditional bifunctional mechanism, i.e., oxide promoting CO oxidation, but rather via hydrous metal oxide shell blocking CO adsorption. An ab initio molecular dynamics (AIMD) simulation indicates that water confined in grain boundaries of the Ru oxide layer and Ru surface can suppress the diffusion and adsorption of CO. This oxide blocking layer approach opens a promising avenue for the design of high CO-tolerant electrocatalysts for fuel cells.

Hydrogen is regarded as an attractive alternative energy carrier due to its high gravimetric energy density and only water production upon combustion. However, due to its low volumetric energy density, there are still some challenges in practical hydrogen storage and transportation. In the past decade, using chemical bonds of liquid organic molecules as hydrogen carriers to generate hydrogen in situ provided a feasible method to potentially solve this problem. Research efforts on liquid organic hydrogen carriers (LOHCs) seek practical carrier systems and advanced catalytic materials that have the potential to reduce costs, increase reaction rate, and provide a more efficient catalytic hydrogen generation/storage process. In this work, we used methanol as a hydrogen carrier to release hydrogen in situ with the single-site Pt 1 /CeO 2 catalyst. Moreover, in this reaction, compared with traditional nanoparticle catalysts, the single site catalyst displays excellent hydrogen generation efficiency, 40 times higher than 2.5 nm Pt/CeO 2 sample, and 800 times higher compared to 7.0 nm Pt/CeO 2 sample. This in-depth study highlights the benefits of single-site catalysts and paves the way for further rational design of highly efficient catalysts for sustainable energy storage applications.