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A simple and efficient cobalt-catalyzed aerobic oxidative dehydrogenative Povarov reaction of tertiary anilines with dihydrofuran has been developed for the synthesis of hexahydrofuro[3,2- c ]quinolines. The one-electron-oxidation involved reaction is performed under mild conditions and only requires simple cobalt salts as a catalyst and dioxygen as a terminal oxidant. [ABSTRACT FROM AUTHOR]

The N–H insertion reaction forms the single addition product exclusively, and does not require slow addition of the diazo component. More importantly, we present the reaction of anilines with both diazoacetates and azodicarboxylates in the presence of catalytic amounts of triarylaminium salt giving the corresponding complex unsymmetrical aminals in high yields. This is the first example of stable radical cation salt promoted proton-transfer-delay three-component reaction. [ABSTRACT FROM AUTHOR]

Abstract: A novel and efficient regioselective Friedel–Crafts alkylation reaction of 2-naphthols with electron-rich enamides or enethers initiated by catalytic amounts of stable radical cation triarylaminium salt has been developed. The processes occur under mild conditions. [Copyright &y& Elsevier]

Abstract: Commercially available stable radical cation triarylaminium salt can be used as an efficient initiator for Friedel–Crafts reaction of indoles with enamides to regioselectively construct complex indole derivatives and for double Friedel–Crafts reaction of indoles with vinyl ethers to offer 3,3′-Bis(indolyl)alkane derivatives. The ready availability of the starting materials and the usefulness of the products make this strategy attractive. [Copyright &y& Elsevier]

Abstract: A novel and efficient chemoselective tandem Friedel–Crafts alkylation/cyclization reaction of glycidic esters with 2-naphthol derivatives initiated by stable radical cation salt (0.5 mol %) has been developed. [Copyright &y& Elsevier]

Abstract: The reaction of chalcone epoxides with 2-naphthyl ethers can be initiated by stable triarylaminium salt. And after subsequent aerobic oxidative aromatization in one pot, a series of polysubstituted naphtho[2,1-b]furans were delivered. [Copyright &y& Elsevier]

Abstract: Triarylaminium salt was disclosed as a highly efficient nonmetallic initiator for the Friedel–Crafts reaction between chalcone epoxides and heteroarenes to construct a series of complex β-heteroaryl α-ketols in mild conditions and with good yields. Chalcone epoxides were presented as valuable halogen-free pre-electrophile in Friedel–Crafts alkylation through the formation of the stabilized benzylic cation intermediates. A plausible radical cation chain mechanism was also proposed. [Copyright &y& Elsevier]

Abstract: A series of phosphate or phosphate–acetate hybrid modified EGCG or EGCG G ring deoxy analogs were synthesized by a convenient semi-synthesis strategy from the abundant natural compound EGCG. [Copyright &y& Elsevier]

Abstract: A pro-drug 8 of a synthetic analog 7 is more active in its antiproliferative activity against human breast cancer MDA-MB-231 cells possessing high catechol-O-methyltransferase (COMT) activity than the pro-drugs of EGCG and the analog 5. The higher activity of 8 is attributed to it not being a substrate of COMT. [Copyright &y& Elsevier]

Abstract: The total and semi syntheses of (2R,3R)-epigallocatechin-3-O-(4-hydroxybenzoate), a novel catechin from Cistus salvifolius, were accomplished. The proteasome inhibition and cytotoxic activities of the synthetic compound and its acetyl derivative were studied and compared with (2R,3R)-epigallocatechin-3-gallate (EGCG), the active component from green tea. [Copyright &y& Elsevier]

Abstract: The reaction of ethyl diazoacetate with aryl imines can be initiated by persistent cation radical salt tris(4-bromophenyl)aminium hexachloroantimonate, giving exclusively cis-aziridine carboxylates. [Copyright &y& Elsevier]

[Display omitted] A copper catalyzed aerobic sp3 C H amination of 3,4-dihydroquinoxalin-2(1H)-ones is developed. This protocol provides a concise method to access 3-aminoquinoxalinone derivatives with good functional-group tolerances, utilizing primary and secondary aliphatic amines as nitrogen sources under mild and simple reaction conditions. It provides a practical approach to the synthesis of pharmaceutical active 3-aminoquinoxalinones. [ABSTRACT FROM AUTHOR]

Abstract: Aromatization of Hantzch 1,4-dihydropyridines was achieved under radical cation salt induced conditions, in which triarylamine radical cation acts as an efficient catalyst to prompt the aerobic oxidation of 1,4-DHPs in a catalytic way. [Copyright &y& Elsevier]

Abstract: A domino process between iminoethyl glyoxylate and N-vinylamides was achieved under the catalytic radical cation salt induced conditions, producing a series of quinoline-2-carboxylates. N-Vinylamides were involved as an acetylene equivalent. A possible mechanism was proposed to rationalize the formation of the products. [Copyright &y& Elsevier]

Abstract: Three-component reaction of alkyl halides, sodium azide with terminal alkynes can be catalyzed by nano-copper particles under ambient conditions. A series of 1,4-disubstituted-1,2,3-triazoles were obtained regioselectively by this one-pot strategy. Nano copper can be reused at least three times without significant deactivation. [Copyright &y& Elsevier]

Bioactive small molecules, hypochlorous acid (HClO) and sulfur dioxide (SO 2), play vital roles in the maintenance of normal physiological function of living organisms. Once their balance is interrupted, it would cause oxidative stress and various diseases. Therefore, monitoring the change of HClO and SO 2 in cellular levels and in vivo is of great significant for exploring their physiological and pathological roles. Herein, we present a dual-site and dual-turn-on fluorescence probe PTBI that could simultaneously monitor HClO and SO 2 in mitochondria by two well-separated emission channels with a difference of 115 nm. The probe exhibited fast response (HClO: < 5 s, SO 2 : <1 min) and low detection limits with 45.8 and 53.2 nM for HClO and SO 2 , respectively. Using the single fluorescence molecule, we not only realized the detection of the basal and exogenous/endogenous levels of HClO and SO 2 , but also achieved the monitoring mitochondrial oxidative stress induced by HClO in living cells and zebrafish. [Display omitted] • PTBI features dual-site and dual-turn-on response to HClO and SO 2 with a sufficient fluorescence signals interval. • PTBI displays fast response to HClO (within 5 s) and SO 2 (within 1 min). • PTBI possesses excellent sensitivity towards HClO and SO 2 with detection limits of 45.8 and 53.2 nM, respectively. • PTBI is successfully applied to detect the basal and exogenous/endogenous levels of HClO and SO 2. • PTBI is applied to monitor the mitochondrial oxidative stress induced by HClO. [ABSTRACT FROM AUTHOR]

Abstract: A tandem cyclization/aromatization of anilines and aldehydes was achieved under catalytic radical cation salt induced conditions, producing a series of 2,3-disubstituted quinolines in good yields. In this reaction, the in situ generated imine tautomerizes to enamine, which acts as a dienophile to participate in the tandem cyclization, and further elimination of the anilino group triggers the aromatization of tetrahydroquinolines, avoiding harsh conditions. [Copyright &y& Elsevier]

Image 1 • A regioselective [3 + 2] cycloaddition reaction of benzoaurones with nitrile imines was developed. • A series of compelling spiro [naphthofuran-2,3′-pyrazoline]-3-ones were efficiently obtained. • The reaction displayed good gram-scale capacity. [ABSTRACT FROM AUTHOR]

• Visible light promoted sulfonylation and sulfonylcarbonylation reactions were presented. • TosMIC was used as the sulfonyl source. • Vinyl sulfones and β-keto sulfones were synthesized in good to high yields. • A reasonable radical involved mechanism is proposed. Visible light promoted sulfonylation and sulfonylcarbonylation reactions of readily available alkenes with TosMIC for the synthesis of valuable vinyl sulfones and β-keto sulfones were described. A reasonable radical involved mechanism is proposed. [ABSTRACT FROM AUTHOR]