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A three-component 1,2-aminooxygenation reaction of 1,3-dienes by dual photoredox and copper catalysis is described. This protocol usesiN/i-aminopyridinium salts as N-centered radical precursors and nucleophilic alcohols as oxygen sources, providing modular and practical access to 1,2-aminoalkoxylation products with good yields and regioselectivity. Preliminary mechanistic studies support the radical property of the reaction and the involvement of N-centered radical intermediates.

Piperazine-derived diazabicycles are privileged structures found in natural products and synthetic chemical entities, including therapeutic agents. Herein, we deciphered the biosynthesis of two unique classes of diazabicyclic alkaloids, fischerazines A-C. Notably, we characterized a multifunctional P450 monooxygenase NfiC that installs

A selective three-component 1,4-difluoroalkylesterification of 1-aryl-1,3-dienes enabled by dual photoredox and copper catalysis is described. This protocol uses commercially available CF

A metal-free, photoredox-catalyzed three-component cyanoalkylfluorination of alkenes under mild and redox-neutral conditions is reported. This protocol features use of readily available alkenes, oxime esters, and cost-effective nucleophilic fluoride reagents, giving diverse cyanoalkylfluorinated products with generally good yields. Excellent functional group tolerance and mild reaction conditions also render this protocol suitable for cyanoalkylfluorination of pharmaceutically relevant molecule-derived alkene.

A visible-light-driven photoredox-catalyzed multicomponent reaction of 2-vinylanilines, sulfonyl chlorides, and sulfur ylides is described. This protocol features redox-neutral mild conditions, a broad substrate scope, and good functional group tolerance, providing access to various sulfonated 2,3-disubstituted indolines. The product can be transformed to a diverse range of functionalized indoles by a selective aromatization/nucleophilic substitution process. Mechanistic investigations suggest that both sulfonyl chlorides and sulfur ylides serve as radical sources, and the reaction proceeds through a sequential radical addition/addition/thermal SN2-substitution process.

A visible-light-driven, copper-catalyzed C(sp3)–O coupling of benzylic radicals with phenols is described for the first time. This operationally simple and robust process features mild conditions, ...

A visible-light-driven, perfluoroalkyl radical-mediated strategy for in situ formation of aza-o-QMs from readily available precursors is reported. Combination of this method with a Bronsted base thus enables an efficient and highly diastereoselective HDA reaction between such photogenerated aza-o-QMs and π-electron-poor systems, aldehydes, providing high yielding and rapid access to valuable, diversely substituted dihydrobenzoxazines. DFT calculation elucidated the origins of stereochemistry of the products and disclosed the concerted property of the process.

A neutral nitrogen radical-mediation strategy, wherein the existing N-H moiety of substrates serves as a neutral nitrogen radical precursor to enable room-temperature intermolecular radical difunctionalization of styrenes under photoredox catalysis, is reported. The reaction shows high functional group tolerance and substrate scope with respect to both components, giving the corresponding products with generally good yields. Preliminary control experiments and DFT calculations are performed to explain the reaction mechanism.

A visible-light-driven, copper-catalyzed C(sp

A visible light photoredox-promoted and nitrogen radical catalyzed [3 + 2] cyclization of vinylcyclopropanes and

Catalytic enantioselective chemical reactions involving highly reactive radical species remain largely unexplored. We report herein for the first time a novel enantioselective radical ring-opening cyanation of redox-active oxime esters by dual photoreodox and copper catalysis. This mild protocol shows good functional group tolerance and broad substrate scope, producing a wide range of optically active alkyl dinitriles with high yields and excellent enantioselectivities, which are difficult to access traditionally.

A visible-light-driven, perfluoroalkyl radical-mediated strategy for in situ formation of aza

A general and efficient Pd/phosphoramidite thioether complex-catalyzed asymmetric N-allylic alkylation of hydrazones with allylic acetates has been developed for the first time. The reaction allows for the preparation of various valuable N-substituted hydrazones with generally good yields and excellent enantioselectivities. Minor structural modification of the ligand resulted in opposite enantiomers, enabling enantiodivergent synthesis of products by the same catalytic system.

The first example of a Pd(OAc)2-catalyzed ring-forming alkene aminoaroylation of unsaturated hydrazones and sulfonamides is described. This protocol features the use of diaryliodonium salts as both oxidants and aryl sources, thus enabling mild reaction conditions, good chemoselectivity, a broad substrate scope, and high functional group tolerance. A wide range of synthetically and biologically important functionalized dihydropyrazoles and isoxazolidines have been obtained in good yields.

A dual visible light photoredox and nickel-catalyzed cross-coupling reaction of 2-arylaziridines and potassium benzyltrifluoroborates is described for the first time. This strategy features high functional group tolerance, exclusive regioselectivity for reaction at the more hindered C-N bond, easily accessible substrates, and mild redox-neutral reaction conditions. A variety of diversely substituted β-substituted amines are obtained in generally good yields.

A visible-light photocatalytic decarboxylative alkyl radical addition cascade reaction of acrylamide-tethered styrenes for the synthesis of benzazepine derivatives is described. This protocol features broad substrate scope, excellent functional group tolerance, and mild reaction conditions, affording the seven-membered rings in good yields. This method was also applied for efficient grafting of the benzazepine scaffold into the pharmaceutically active ursolic acid scaffold.

Here we report an aerobic Pd(0) catalyzed C2-H functionalization of indoles and pyrroles with tethered N-methoxylamide as the directing group. A Pd(0)-initiated mechanism overcomes the directing or poisoning effect from a wide range of heterocycles including pyridine, pyrimidine, and thiazole. The imidazo[1,5-a]indole products are transformed to bioactive analogs after one-step manipulations, demonstrating the potential utility of this reaction in drug discovery.

A novel photocatalytic hydrazonyl radical-mediated radical cyclization/allylation cascade reaction of β,γ-unsaturated hydrazones is developed using allyl sulfones and Morita-Baylis-Hillman adduct as allyl sources, which provides an efficient and practical access to various diversely functionalized dihydropyrazoles and tetrahydropyridazines. The reaction is enabled by controllable generation of hydrazonyl radicals via an oxidative deprotonation electron transfer strategy and selective trapping of the resultant C-centered radicals under visible light irradiation.

A general and efficient visible light photocatalytic α-amino carbon radical-based cascade reaction of aroylhydrazones has been described. This protocol tolerates a wide array of α-silylamines and aroylhydrazones to afford the corresponding diversely functionalized hydrazide-containing chroman-2-ones and dihydroquinolin-2-ones in generally good yields with excellent diastereoselectivities.

A light-driven, metal-free, and iminyl radical-mediated ring-opening C-C bond cleavage/addition cascade of O-4-methoxybenzyl oxime ethers and alkenes is described for the first time. The reaction shows a broad substrate scope and high functional group compatibility with both components, giving the corresponding valuable oxo nitriles in generally good yields. Key to the success of this protocol is the generation of cyclic iminyl radicals from the O-4-methoxybenzyl oxime ethers via a photocatalytic hydrogen atom transfer (HAT) process. The proposed main pathway is also supported by the preliminary mechanistic studies.

It was demonstrated that 3-olefinic oxindoles could generate zwitterionic enolate species with tertiary phosphines and undergo C–C bond formation with various electrophiles in an interrupted Morita–Baylis–Hillman-type reaction manner, followed by a dephosphoration process. Although the in situ formation of phosphorus-ylide intermediates was observed, no Wittig reaction was detected, even in the presence of excess formaldehyde. Moreover, excellent enantioselectivity for the construction of quaternary stereogenic centers was induced with chiral phosphines. Deuterium experiments and density functional theory calculations were conducted to elucidate the reaction mechanism.

A ligand-free, palladium-catalyzed aminoarylation reaction of the unactivated alkenes in β,γ-unsaturated hydrazones is described. This protocol enables efficient and simultaneous formation of C(sp3)–N and C(sp3)–C(sp2) bonds under mild conditions, providing a practical and general approach to various diversely substituted dihydropyrazoles in generally good yields, without the use of any stoichiometric external oxidant.

Intermolecular benzylic methylene functionalization of exo-cyclic enol ethers has been achieved using imines as reagents and potassium tert-butoxide as the catalyst. Depending on the solvent used, the reaction proceeds by two pathways. In THF, an addition/elimination reaction of exo-cyclic enol ethers with imines provides dihydroisobenzofuran derivatives in good yield. In DMSO, an addition/ring-opening/cyclization cascade reaction occurs with unexpected cleavage of C-O and C-C bonds, affording isoquinolin-1(2H)-one products in high yield under ambient reaction conditions.

An asymmetric nucleophilic addition/protonation reaction of 3-substituted oxindoles and ethyl 2-phthalimidoacrylate has been described. This strategy can give direct access to C(γ)-tetrasubstituted α-amino acid derivatives bearing 1,3-nonadjacent stereocenters with up to 98% yield, 94:6 dr, and99% ee. Dual activation is proposed in the transition state, and the opposite enantiomers can be obtained simply by changing cinchonidine-derived catalyst to the cinchonine analogue.

A highly enantioselective organocatalytic intermolecular conjugate addition of oximes to β-nitroacrylates has been developed. The highly functionalized adducts obtained are valuable precursors for asymmetric synthesis, as demonstrated by the synthesis of β(2,2)-amino acids and oxazolidin-2-ones.

A general visible light induced photoredox-catalyzed radical trifluoromethylation/cyclization cascade of β-aryl-β,γ-unsaturated hydrazones and oximes is described. The protocol enables an efficient access to various densely functionalized and biologically important CF3-containing dihydropyrazoles and isoxazolines with generally high yields.

A general and efficient Pd/sulfoxide-phosphine complex-catalyzed direct asymmetric N-allylic alkylation of indoles has been developed to allow for the preparation of various N-allylated indoles in generally good yields with excellent enantioselectivities. This catalytic system could also be extended to other N-containing heterocycles with good results.

A highly stereoselective asymmetric 1,4-addition of diarylphosphines to α,β-unsaturated aldehydes catalyzed by a bis(phosphine) pincer-Pd complex has been developed for the synthesis of chiral phosphines with excellent stereoselectivity (up to 98% ee) under mild conditions. The application of the current method to the synthesis of enantiopure bisphosphine and its pincer-Pd complex has also been demonstrated.

An unprecedented three-component coupling reaction of arynes, α-bromo carbonyl compounds, and DMSO triggered by insertion of arynes into the S═O bond of DMSO has been developed. The reaction can generate a wide range of multisubstituted aryl methyl thioethers in good yields, wherein DMSO serves as both methylthiolation reagent and oxygen source.

Rhodium-catalyzed addition-cyclization of hydrazines with alkynes has been achieved to afford highly substituted pyrazoles under mild conditions. The cascade reaction involves two transformations: addition of the C-N bond of hydrazines to alkynes via unexpected C-N bond cleavage and intramolecular dehydration cyclization.

A catalytic asymmetric aza-Michael−Michael addition cascade of anilines to nitroolefin enoates in the presence of chiral bifunctional thiourea catalysts has been disclosed. This reaction provides a mild and efficient approach to polysubstituted chiral 4-aminobenzopyrans bearing three consecutive stereocenters in high yields with excellent stereoselectivities.

A hydrogen bonding-mediated double Michael addition-aromatization cascade of 2-propenylindoles and nitroolefins has been disclosed. The methodology allows an efficient synthesis of diverse and structurally complex tetrahydrocarbazoles in good to excellent enantioselectivities and diastereoselectivities.

Two coumarin-based spiropyran derivatives were synthesized and characterized in two steps to explore their photochromic properties. Both prepared compounds are sensitive to UV light and change colors upon irradiation. The resulting photogenerated zwitterions revert to the original compounds while being heated. A new family of organic photochromic colorants is introduced.

[reaction: see text] Readily tunable and bifunctional L-prolinamides as novel organocatalysts have been developed, and their catalytic activities were evaluated in the direct asymmetric Aldol reactions of various aromatic aldehydes and cyclohexanone. High isolated yields (up to 94%), enantioselectivities (up to 99% ee), and anti-diastereoselectivities (up to 99:1) were obtained under the optimal conditions.