Correction: (Thio)chromenone derivatives exhibit anti-metastatic effects through selective inhibition of uPAR in cancer cell lines: discovery of an uPAR-targeting fluorescent probe.

Correction for '(Thio)chromenone derivatives exhibit anti-metastatic effects through selective inhibition of uPAR in cancer cell lines: discovery of an uPAR-targeting fluorescent probe' by So-Young Chun , , 2025, https://doi.org/10.1039/D4CC05907G.

Catalytic Aerobic Carbooximation of Alkenes Using Secondary Nitroalkanes as Both α-Nitro Alkyl Radical and Nitrogen Monoxide Sources.

Aerobic nitro-nitrite isomerization of secondary nitroalkanes is postulated to proceed via the intermediacy of the α-nitro alkyl radical, where the corresponding Nef-type products, ketones, and nitrogen monoxide can be obtained as byproducts. To explore the catalytic aerobic carbooximation of alkenes using secondary nitroalkanes, phase-transfer catalysis of KSeCN and TBAI has been developed. The current aerobic carbooximation of alkenes utilizes nitroalkanes as both radical and nitrogen monoxide sources in water without external oxidants and prefunctionalized nitroalkanes.

(Thio)chromenone derivatives exhibit anti-metastatic effects through selective inhibition of uPAR in cancer cell lines: discovery of an uPAR-targeting fluorescent probe.

A class of (thio)chromenone derivatives has been identified as suitable ligands for uPAR, a glycoprotein with a prognostic value in a large number of human cancers. The (thio)chromenone agents actively inhibited the binding of uPAR to uPA with a binding affinity of 18.6 nM, reducing cell migration in the wound healing assay by up to 40% without apparent cell motility.

Visible Light-Induced Three-Component Alkoxyalkylation of Alkenes with α-Halocarbonyls and Alcohols.

A visible-light-induced three-component alkoxyalkylation of alkenes has been developed under the photocatalysis of -Ir(ppy). The alkene substrate scope included aryl and aliphatic alkenes as well as electron-rich and electron-deficient alkenes, allowing the facile coupling with a diverse array of α-halocarbonyl compounds. The redox potential-guided orchestration of radical processes with precision allows rapid access to highly functionalized products that are useful building blocks in organic synthesis.

Visible Light-Induced Radical Cascade Functionalization of Quinoxalin-2(1)-ones: Three-Component 1,2-Di(hetero)arylation Approach with Styrenes and Thianthrenium Salts.

The additive-free visible light-induced three-component 1,2-di(hetero)arylation of styrenes was developed using quinoxalin-2(1)-ones and thianthrenium salts. The purple visible light excitable quinoxalin-2(1)-ones were utilized for the single-electron transfer to aryl thianthrenium salts, where the generated aryl radical species underwent the addition cascade to styrenes and quinoxalin-2(1)-ones. The direct aryl radical addition to quinoxalin-2(1)-ones also led to the formation of a side product, C3-aryl quinoxalin-2(1)-ones, capable of a photoredox process to help the formation of 1,2-di(hetero)arylation products.

Photoredox-Catalyzed 1,4-Peroxidation-Sulfonylation of Enynones: A Three-Component Radical Coupling Approach for the Synthesis of Highly Functionalized Allenes.

An Eosin Y-catalyzed visible light-promoted 1,4-peroxidation-sulfonylation of enynones was achieved to give tetrasubstituted allenes. The photoredox catalysis of Eosin Y allowed the concomitant formation of peroxy and sulfonyl radicals, where the preferential peroxy radical addition to the alkene moiety of enynones resulted in the subsequent α-keto radical-sulfonyl radical cross couplings. The developed photoredox catalysis of Eosin Y demonstrates a regioselective 1,4-diradical addition strategy, opening up a new possibility of diradical functionalization of conjugate systems.

Visible-Light-Promoted Aryl Cation Formation: Aromatic S1 Reactions of Areneazo-2-(2-nitro)propanes.

The visible light excitation of areneazo-2-(2-nitro)propane·HCl salts generated the singlet aryl cation that readily underwent aromatic S1 reactions with a variety of nucleophiles. The in situ generated singlet aryl cation was stabilized by a counter nitronate anion that prevented other intersystem crossing and single electron transfer processes. With the improved safety features of neutral areneazo-2-(2-nitro)propane derivatives, the current visible-light-promoted aromatic S1 reactions provide an alternative aryl C-X bond forming strategy.

Chemodivergent Sulfonylation of Enynones via Ionic and Radical Addition Modes of Sulfinic Acids.

Different addition modes of sulfinic acids were developed for the chemodivergent sulfonylation of enynones, where the ionic sulfonylation to an alkyne moiety of enynones was effected through a salt-controlled -addition pathway. The radical sulfonylation of an alkene moiety also provided the stereodefined sulfonylated alkenes. A one-pot tandem sequence of the Ti(O-Pr)-catalyzed α-vinyl aldol condensation of ()-β-chlorovinyl ketones followed by the chemodivergent sulfonylations was also explored, allowing for ready access to highly substituted dienes and enynes.

Catalytic Aerobic N-Nitrosation by Secondary Nitroalkanes in Water: A Tandem Diazotization of Aryl Amines and Azo Coupling.

Secondary nitroalkanes underwent oxygen-mediated nitro-nitrite isomerization, serving as versatile N-nitrosating agents under aerobic conditions. To capitalize on the newly discovered aerobic nitro-nitrite isomerization phenomenon, a phase-transfer catalysis system employing KSeCN and TBAI was developed, in which the tandem diazotization and azo coupling with nitroalkanes as well as N-nitrosation of amines were accomplished. The current tandem diazotization and azo coupling strategy provides a facile synthesis of areneazo-2-(2-nitro)propane derivatives, a safe synthetic alternative to aryl diazonium salts.

One-Pot Tandem Nickel-Catalyzed α-Vinyl Aldol Reaction and Cycloaddition Approach to [1,2,3]Triazolo[1,5-]quinolines.

A one-pot tandem approach to [1,2,3]triazolo[1,5-]quinolines was developed from ()-β-chlorovinyl ketones and 2-azidoaryl carbonyls using a sequence of α-vinyl aldol and azide-alkyne cycloaddition reactions. In particular, the intramolecular azide-alkyne cycloaddition of allenol intermediates was readily promoted by a synergistic action of NEt and nickel catalysts. Given that the [1,2,3]triazolo[1,5-]quinolines are useful synthetic precursors to α-diazoimines through ring-chain isomerization process, the subsequent denitrogenative transformations should provide ready access to valuable heterocyclic compounds.

Visible-Light-Induced Three-Component Selenofunctionalization of Alkenes: An Aerobic Selenol Oxidation Approach.

A photocatalyst-free visible-light-induced selenofunctionalization of alkenes has been developed using a variety of nucleophiles. The homolytic scission of diselenides under visible-light conditions coupled with the aerobic selenol oxidation to diselenides allowed the successful implementation of three-component selenofunctionalization under visible-light irradiation in open-air conditions. The mechanistic studies revealed the critical role of oxygen content in a reaction medium, where the electron transfer process from the carbon-based radicals to either molecular oxygen or selenyl radicals was controlled.

-Naphthoquinone-Catalyzed Aerobic Hydrodeamination of Aryl Amines via De-diazotization of Aryl Diazonium Species.

The catalytic diazotization of aryl amines was developed using -naphthoquinone catalyst under aerobic conditions, where the 2-nitropropane served as a source of nitrosonium ion. The catalytic generation of diazonium species from aryl amines was further explored in the hydrode-diazotization to give the corresponding products. The mechanistic studies indicated the involvement of aryl radical species that readily underwent the radical cyclization to alkenes as well as the halogen abstraction reactions.

Visible-Light-Promoted Photoaddition of -Nitrosopiperidines to Alkynes: Continuous Flow Chemistry Approach to Tetrahydroimidazo[1,2-]pyridine 1-Oxides.

The photoaddition of -nitrosopiperidines to terminal alkynes was effected under visible-light irradiation, in which a novel synthetic access to tetrahydroimidazo[1,2-]pyridine 1-oxides was achieved via the dehydrogenative cycloisomerization of β-nitroso enamine intermediates. The decomposition pathways of -nitrosamines, alkynes, and β-nitroso enamine intermediates were better handled in a continuous flow setting through the diffusion control of chemical species that negatively affected the formation of tetrahydroimidazo[1,2-]pyridine 1-oxides under batch reaction conditions.

Continuous Flow Synthesis of 1,4-Benzothiazines Using Ambivalent Reactivity of ()-β-Chlorovinyl Ketones: A Point of Reaction Control Enabled by Flow Chemistry.

A continuous flow system to 1,4-benzothiazines was developed using the point of reaction control, where the ambivalent ()-β-chlorovinyl ketones and 2,2'-dithiodianilines were confined in a diffusion controlled flow setting. The successful segregation of reactive chemical species in a flow setting allowed more defined reaction pathways that are not feasible in traditional batch reaction conditions. The point of reaction control in flow systems helps to execute the reactions often plagued with the concurrent generation of multiple chemical species.

Bioinspired -Naphthoquinone-Catalyzed Aerobic Oxidation of Alcohols to Aldehydes and Ketones.

A biomimetic alcohol dehydrogenase (ADH)-like oxidation protocol was developed using an -naphthoquinone catalyst in the presence of a catalytic amount of base. The developed organocatalytic aerobic oxidation protocol proceeds through the intramolecular 1,5-hydrogen atom transfer of naphthalene alkoxide intermediates, a mechanistically distinctive feature from the previous alcohol dehydrogenase mimics that require metals in the active form of catalysts. The ADH-like aerobic oxidation protocol should provide green alternatives to the existing stoichiometric and metal-catalyzed alcohol oxidation reactions.

One-Pot Synthesis of -Hydroxypyrroles via Soft α-Vinyl Enolization of ()-β-Chlorovinyl Ketones: A Traceless Arylsulfinate Mediator Strategy.

A traceless arylsulfinate mediator strategy has been developed to switch the reaction course of β-chlorovinyl ketones with -hydroxyamine. The soft α-vinyl enolization of ()-β-chlorovinyl ketones was conducted in the presence of sodium arylsulfinate to give transient alkenyl sulfones that in turn reacted with NHOH to give novel access to -hydroxypyrroles. The mechanistic studies revealed the initial formation of oxazine intermediates that rearranged to thermodynamically stable aromatic products, -hydroxypyrroles, under microwave-assisted heating conditions.

Silver-Catalyzed Asymmetric Desymmetrization of Cyclohexadienones via Van Leusen Pyrrole Synthesis.

A catalytic asymmetric desymmetrization of cyclohexadienones was accomplished via Van Leusen pyrrole synthesis in the presence of a chiral silver catalyst. The ready access to chiral-fused pyrrole derivatives is attributed to the identification of a suitable isocyanomethyl sulfone surrogate, NasMIC. The current Ag(I)-chiral phosphino-carboamide ligand system can be extended to the kinetic resolution of racemic cyclohexadienones, capitalizing on the differentiated reactivity of chiral quaternary complexes from AgSbF, chiral ligand (*), cyclohexadienone, and NasMIC.

One-Pot Direct Oxidation of Primary Amines to Carboxylic Acids through Tandem ortho-Naphthoquinone-Catalyzed and TBHP-Promoted Oxidation Sequence.

Biomimetic oxidation of primary amines to carboxylic acids has been developed where the copper-containing amine oxidase (CuAO)-like o-NQ-catalyzed aerobic oxidation was combined with the aldehyde dehydrogenase (ALDH)-like TBHP-mediated imine oxidation protocol. Notably, the current tandem oxidation strategy provides a new mechanistic insight into the imine intermediate and the seemingly simple TBHP-mediated oxidation pathways of imines. The developed metal-free amine oxidation protocol allows the use of molecular oxygen and TBHP, safe forms of oxidant that may appeal to the industrial application.

Oxidation Potential-Guided Electrochemical Radical-Radical Cross-Coupling Approaches to 3-Sulfonylated Imidazopyridines and Indolizines.

Oxidation potential-guided electrochemical radical-radical cross-coupling reactions between N-heteroarenes and sodium sulfinates have been established. Thus, simple cyclic voltammetry measurement of substrates predicts the likelihood of successful radical-radical coupling reactions, allowing the simple and direct synthetic access to 3-sulfonylated imidazopyridines and indolizines. The developed electrochemical radical-radical cross-coupling reactions to sulfonylated N-heteroarenes boast the green synthetic nature of the reactions that are oxidant- and metal-free.

Correction: Recent advances in the copper-catalyzed aerobic C-H oxidation strategy.

Correction for 'Recent advances in the copper-catalyzed aerobic C-H oxidation strategy' by Hun Young Kim et al., Org. Biomol.

Recent advances in the copper-catalyzed aerobic C-H oxidation strategy.

The interplay between copper catalysts and molecular oxygen provides the opportunity to control the promiscuous catalytic behaviors in aerobic Csp3-H bond oxidations without using stoichiometric amounts of oxidants. This mini-review aims to cover the Cu-catalyzed aerobic benzylic and α-carbonyl Csp3-H oxidations and that of the carbon next to an amine group in the past five years. The development of tandem multicomponent reactions employing aerobic Csp3-H bond oxidations will be discussed to highlight the controlled catalyst behaviors and the catalyst interactions between multiple reaction components.

Visible-Light-Induced Photoaddition of -Nitrosoalkylamines to Alkenes: One-Pot Tandem Approach to 1,2-Diamination of Alkenes from Secondary Amines.

The generation of aminium radical cation species from -nitrosoamines is disclosed for the first time through visible-light excitation at 453 nm. The developed visible-light-promoted photoaddition reaction of -nitrosoamines to alkenes was combined with the -NQ-catalyzed aerobic oxidation protocol of amines to telescope the direct handling of harmful -nitroso compounds, where the desired α-amino oxime derivatives were obtained in a one-pot tandem N-nitrosation and photoaddition sequence.

One-Pot Tandem -Naphthoquinone-Catalyzed Aerobic Nitrosation of -Alkylanilines and Rh(III)-Catalyzed C-H Functionalization Sequence to Indole and Aniline Derivatives.

The nitroso group served as a traceless directing group for the C-H functionalization of -alkylanilines, ultimately removed after functioning either as an internal oxidant or under subsequent reducing conditions. The unique ability of -NQ catalysts to aerobically oxidize the -alkylanilines without using solvents and stoichiometric amounts of oxidants has rendered the new opportunity to develop the telescoped catalyst systems without a need for directly handling the hazardous -nitroso compounds.

-Naphthoquinone-catalyzed aerobic oxidation of amines to fused pyrimidin-4(3)-ones: a convergent synthetic route to bouchardatine and sildenafil.

A facile access to fused pyrimidin-4(3)-one derivatives has been established by using the metal-free -naphthoquinone-catalyzed aerobic cross-coupling reactions of amines. The utilization of two readily available amines allowed a direct coupling strategy to quinazolinone natural product, bouchardatine, as well as sildenafil (Viagra™) in a highly convergent manner.