Photoinduced copper-catalyzed asymmetric cyanoalkylalkynylation of alkenes, terminal alkynes, and oximes.

The asymmetric dicarbofunctionalization of alkenes a radical relay process can provide routes to diverse hydrocarbon derivatives. Three-component carboalkynylation, limited to particular alkyl halides and using readily available cycloketone oxime esters as redox-active precursors, is restricted by the available pool of suitable chiral ligands for broadening the redox potential window of copper complexes and simultaneously creating the enantiocontrol environment. Herein, we report a new hybrid tridentate ligand bearing a guanidine-amide-pyridine unit for photoinduced copper-catalyzed cyanoalkylalkynylation of alkenes.

Visible-light-driven asymmetric aldol reaction of ketones and glycinates synergistic Lewis acid/photoredox catalysis.

Visible-light-driven direct asymmetric α-C(sp)-H bond functionalization of glycinate provides a direct and efficient route for the synthesis of diverse optically enriched α-amino acid derivatives. However, asymmetric coupling between glycinate radical species and ketones faces significant challenges, including competitive pathways, mutable intermediates, as well as congested stereogenic centers. Herein, we disclose the first example for the asymmetric photocatalytic synthesis of a diverse array of β-diaryl-β-hydroxy-α-amino acetate derivatives from glycinates and heteroaryl ketones through the synergistic catalysis of achiral iridium photoredox catalyst and chiral lanthanide Lewis acid catalysts.

Exclusive catalytic hydrogenation of nitrobenzene toward -aminophenol over atomically precise Au(SR) clusters.

Despite the advances in devising green methodologies for selective hydrogenation of nitrobenzene toward -aminophenol, it is still difficult to realize -aminophenol as the exclusive product in heterogeneous metal catalysis, as the excessive hydrogenation of nitrobenzene usually results in the aniline byproduct. Herein we report that a metal cluster containing 36 gold atoms capped by 24 thiolate ligands provides a unique pathway for nitrobenzene hydrogenation to achieve a -aminophenol selectivity of ∼100%. The gold cluster can efficiently suppress the over-hydrogenation of amino groups hydroxyl rearrangement with the aid of water and sequentially the proton transfer promoted by acid toward -aminophenol.

Tandem catalytic allylic C-H amination and asymmetric [2,3]-rearrangement bimetallic relay catalysis.

A bimetallic relay catalysis protocol for tandem allylic C-H amination and asymmetric [2,3]-sigmatropic rearrangement has been developed with the use of an achiral Pd catalyst and a chiral ,'-dioxide-Mg complex in a one-pot operation. A series of anti-α-amino derivatives containing two stereogenic centers were prepared from readily available allylbenzenes and glycine pyrazolamide with good yields and high stereoselectivities. Moreover, the synthetic potential of this protocol was further demonstrated by the product transformations, and a catalytic cycle was proposed to illustrate the reaction process.

Correction: Asymmetric catalytic [1,3]- or [3,3]-sigmatropic rearrangement of 3-allyloxy-4-chromenones and their analogues.

[This corrects the article DOI: 10.1039/D4SC02201G.].

Synergistically activating nucleophile strategy enabled organocatalytic asymmetric P-addition of cyclic imines.

Herein, we present an attractive organocatalytic asymmetric addition of P-nucleophiles to five-membered cyclic -sulfonyl imines facilitated by phosphonium salt catalysis, enabling the highly enantioselective synthesis of tri- and tetra-substituted cyclic phosphorus-containing benzosultams. With this protocol, various cyclic α-aminophosphonates were efficiently synthesized with high yields and exceptional enantioselectivities (up to >99% ee) under mild reaction conditions. The utility and practicality of this method were demonstrated through gram-scale reactions and straightforward elaborations.

Mild ketyl radical generation and coupling with alkynes enabled by Cr catalysis: stereoselective access to -exocyclic allyl alcohols.

The mild catalytic generation of ketyl radicals for organic transformations remains an unsolved issue, although it facilitates the discovery of metal-catalyzed reactions with the features of high functional group tolerance. Here, we report the generation of the ketyl radicals and coupling with alkynes that was enabled by cost-effective chromium catalysis, allowing for the formation of valuable -exocyclic allyl alcohols with high stereo- and chemoselectivity. A broad range of synthetically useful functional groups that are sensitive to strong reductants are compatible with the catalytic system, providing access to diverse substituted -exocyclic allyl alcohols under mild conditions.

Asymmetric catalytic [1,3]- or [3,3]-sigmatropic rearrangement of 3-allyloxy-4-chromenones and their analogues.

A highly efficient asymmetric [1,3]- and [3,3]-O-to-C sigmatropic rearrangement of 3-allyloxy-4-chromenones and their analogues was developed. Chiral ,'-dioxide complexes of 3d late transition metal complexes enabled two mechanistically different processes, giving a series of optically active 2,2-disubstituted chromane-3,4-diones and 2-allyl-3-hydroxy-4-chromen-4-ones as well as their related compounds in excellent yield and enantioselectivity. Systemic mechanistic studies and DFT calculation revealed the nature of the vinyl ether unit of the substrate, which biased regioselectivity a stepwise tight ion pair pathway and a concerted pericyclic pathway, respectively.

Highly selective and additive-free Pd(OAc)/CPP catalyzed hydroaminocarbonylation of alkynes.

Herein, the synthesis of branched α,β-unsaturated amides by a hydroaminocarbonylation reaction of alkynes with various amine substrates such as aromatic amines, aliphatic amines, solid amine sources like NHHCO, and even strongly basic piperidines is reported, using a Pd(OAc)/hybrid N-heterocyclic carbene-phosphine-phosphine (CPP) catalytic system. The reactions feature no additives, wide substrate scope, high selectivity (b/l > 99 : 1) and excellent yields. Mechanistic studies have disclosed that the reaction takes place a palladium hydride pathway.

Efficacy and advantage of immunotherapy for melanoma intramuscular co-expression of plasmid-encoded PD-1 and CTLA-4 scFvs.

Immunotherapy, in the shape of immune checkpoint inhibitors (ICIs), has completely changed the treatment of cancer. However, the increasing expense of treatment and the frequency of immune-related side effects, which are frequently associated with combination antibody therapies and Fc fragment of antibody, have limited the patient's ability to benefit from these treatments. Herein, we presented the therapeutic effects of the plasmid-encoded PD-1 and CTLA-4 scFvs (single-chain variable fragment) for melanoma an optimized intramuscular gene delivery system.

Signal amplified colorimetric nucleic acid detection based on autocatalytic hairpin assembly.

Herein, a nucleic acid assay based on autocatalytic hairpin assembly (ACHA) was proposed. In this system, two split G-quadruplex sequences were integrated into H1 and H2, respectively. And a DNA strand with the same sequence to target DNA was integrated into the assistant hairpin H3.

Iron-catalyzed asymmetric inverse-electron-demand hetero-Diels-Alder reaction of dioxopyrrolidines with simple olefins.

The asymmetric catalytic inverse-electron-demand hetero-Diels-Alder reaction of dioxopyrrolidines with a variety of simple olefins has been accomplished, significantly expanding the applicability of this cyclization to both cyclic hetero-dienes and dienophiles. A new type of strong Lewis acid catalyst of ferric salt enables the LUMO activation of dioxopyrrolidines formation of cationic species, this method yields a range of bicyclic dihydropyran derivatives with exceptional outcomes, including high yields (up to 99%), diastereoselectivity (up to 99 : 1) and enantioselectivity (up to 99% ee) under mild conditions. This facile protocol was available for the late-stage modification of several bioactive molecules and transformation into macrocycle molecules as well.

Realizing highly efficient deep-blue organic light-emitting diodes towards Rec.2020 chromaticity by restricting the vibration of the molecular framework.

Deep-blue organic light-emitting diodes (OLEDs) with narrow emission spectra and high efficiency, meeting the Rec.2020 standard, hold significant promise in the realm of 4K/8K ultrahigh-definition displays. However, the development of light-emitting materials exhibiting both narrowband emission and high efficiency, particularly in the realm of deep-blue thermally activated delayed fluorescence (TADF), confronts substantial challenges.

Chiral cobalt(ii) complex-promoted asymmetric -Claisen rearrangement of allyl α-naphthol ethers.

Due to experiencing a challenging dearomatization process, the aromatic sigmatropic rearrangement of allyl naphthyl ethers is a difficult yet efficient method to build useful naphthalenone skeletons. Here, we report a -Claisen rearrangement-based asymmetric dearomatization of allyl α-naphthol ethers enabled by a ,'-dioxide/Co complex. A variety of naphthalenones were obtained in moderate to good yields with good to excellent ee values.

Two-dimensional mesoporous metals: a new era for designing functional electrocatalysts.

Two-dimensional (2D) mesoporous metals contribute a unique class of electrocatalyst materials for electrochemical applications. The penetrated mesopores of 2D mesoporous metals expose abundant accessible undercoordinated metal sites, while their 2D nanostructures accelerate the transport of electrons and reactants. Therefore, 2D mesoporous metals have exhibited add-in structural functions with great potential in electrocatalysis that not only enhance electrocatalytic activity and stability but also optimize electrocatalytic selectivity.

Efficient electrocatalytic oxygen reduction reaction of thermally optimized carbon black supported zeolitic imidazolate framework nanocrystals under low-temperature.

Turning commercially available low-cost conducting carbon black materials into functional electrocatalytic electrode media using simple surface chemical modification is a highly attractive approach. This study reports on remarkably enhanced oxygen electrocatalytic activity of commercially available Ketjenblack (KB) by growing a non-precious cobalt metal-based zeolitic-imidazolate framework (ZIF-67) at room temperature in methanol solution followed by a mild thermolysis. The resulting Co@CoO nanoparticle decorated nitrogen-doped KB derived from the optimized ZIF-67 : KB weight ratio of hybrid samples at 500-600 °C shows high performance for the oxygen reduction reaction (ORR) with impressive and values of ∼0.

Bimetallic tandem catalysis-enabled enantioselective cycloisomerization/carbonyl-ene reaction for construction of 5-oxazoylmethyl α-silyl alcohol.

A bimetallic tandem catalysis-enabled enantioselective cycloisomerization/carbonyl-ene reaction was developed. The reaction proceeded well with a broad range of -propargylamides and acylsilanes, affording the target chiral 5-oxazoylmethyl α-silyl alcohols in up to 95% yield and 99% ee under mild conditions. Importantly, this facile protocol was available for the late-stage modification of several bioactive molecules.

Isotope-encoded tetrahedral DNA for multiple SARS-CoV-2 variant diagnosis.

The evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed an unprecedented demand for accurate and cost-effective diagnostic assays to discriminate between different variants. Whilst many bioassays have been successfully demonstrated for SARS-CoV-2 detection, diagnosis of its variants remains challenging and mainly relies on time-consuming and costly sequencing techniques. Herein, we proposed a triplevalent tetrahedral DNA nanostructure (tTDN) with three overhang isotope probes capable of multiplex simultaneous analysis.

Visible-light-induced chemo-, diastereo- and enantioselective α-C(sp)-H functionalization of alkyl silanes.

A catalytic asymmetric α-C(sp)-H functionalization of alkyl silanes with benzosultams was realized by merging photoredox and chiral Lewis acid catalysis. The key to success was the choice of photocatalyst with an appropriate redox potential and non-nucleophilic solvent, providing a novel entry to chiral organosilanes containing two adjacent tri- and tetra-substituted stereocenters with high to efficient diastereo- and enantioselectivity (up to 99% ee, 94 : 6 dr) under mild reaction conditions. Based on the control experiment and spectral analysis, an initial single electron transfer reduction of a benzosultam-triggered simultaneous or stepwise electron transfer/proton transfer process was proposed to rationalize the favored C(sp)-H functionalization rather than desilylation.

Regioselective C-H alkylation of anisoles with olefins by cationic imidazolin-2-iminato scandium(iii) alkyl complexes.

A new type of rare-earth alkyl complexes supported by monoanionic imidazolin-2-iminato ligands were synthesised and structurally characterised by X-ray diffraction and NMR analyses. The utility of these imidazolin-2-iminato rare-earth alkyl complexes in organic synthesis was demonstrated by their performance in highly regioselective C-H alkylation of anisoles with olefins. With as low as 0.

Asymmetric and zwitterionic Blatter diradicals.

Asymmetric diradical molecular systems with different resonance mechanisms are largely unexplored. Herein, two conjugated asymmetric diradicals with Blatter and phenoxyl moieties (pBP and mBP) have been synthesized and studied in depth. A complete set of spectroscopic, X-ray crystallographic and magnetic techniques, together with quantum chemical calculations, have been used.

Asymmetric synthesis of complex tricyclo[3.2.2.0]nonenes from racemic norcaradienes: kinetic resolution Diels-Alder reaction.

Herein, the enantioselective synthesis of complex tricyclo[3.2.2.

Recent advances in metal-catalysed asymmetric sigmatropic rearrangements.

Asymmetric sigmatropic rearrangement is a powerful organic transformation substrate-reorganization to efficiently increase molecular complexity from readily accessible starting materials. In particular, a high level of diastereo- and enantioselectivity can be readily accessed through well-defined and predictable transition states in [3,3], [2,3]-sigmatropic rearrangements, which have been widely applied in the synthesis of various chiral building blocks, natural products, and pharmaceuticals. In recent years, catalytic asymmetric sigmatropic rearrangements involving chiral metal complexes to induce stereocontrol have been intensively studied.