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We have disclosed a new radical-mediated decarboxylative C(sp3)–N cross-coupling of diacyl peroxides with nitrogen nucleophiles. The primary and secondary alkyl radicals derived from corresponding diacyl peroxides were generated by copper catalysis or by merging copper catalysis and photoredox catalysis, respectively. Various N-alkyl nitrogen nucleophiles, including indazoles, triazoles, indoles, purine, carbazole, anilines, and sulfonamide, were provided with a broad substrate scope and good functional group tolerance.

A general, ideal atom utilization electrochemical technology to enable alkene alkoxyhalogenation and organohalide dehalogenation in one pot is presented. This technology is highlighted by convergent strategy integrating several reactions, such as alkene alkoxyhalogenation, organohalide dehalogenation, and dehalogenation deuteration. Experimental data suggest that alkenes have the lowest oxidation potential, which lead to anodic conversion of the C═C bond to the radical cation intermediates, and cathodic transformations of organohalides, including alkyl and aryl halides, as the nucleophilic halogen sources.

This study elucidates the mechanisms and principles governing chemoselectivity in synthesizing two distinct N-heterocycles, benzimidazole thiazine and benzothiazole imidazole, through BF3•OEt2-catalyzed cyclization reactions of propargyl alcohols with benzimidazole thiols. Employing density functional theory calculations, we highlight the crucial role of fluorine source in influencing chemoselectivity. In DCM, BF3, as the catalytic center, coordinates with propargyl alcohol’s hydroxyl group to form a precursor. Conversely, in DMF, [BF2•DMF]+, formed from DMF and BF3•OEt2, acts as the catalytic center, activating the propargyl alcohol’s hydroxyl group. The mechanisms in both solvents involve sequential steps: B–O bond formation, C–O bond cleavage, S–C bond formation, hydrogen atom transfer (HAT), cyclization, and deprotonation. A notable difference is the HAT process: in DCM, it follows a 1,5-HAT process, while in DMF, BF4–formation from DMF and BF3•OEt2provides a fluorine source and introduces steric hindrance, favoring a 1,6-HAT process and leading to unique chemoselectivity. This pioneering research showcases the impact of DMF on cyclization reactions, offering valuable insights for comprehending and designing reactions driven by fluorine sources. Crucially, our results propose an innovative reaction mechanism featuring lower potential energy surfaces, enhancing our understanding of the intricate interplay among reactants, catalysts, and solvents.

Water hyacinth was modified by citric acid to prepare a carboxyl-functionalized water hyacinth (CWH) adsorption material. The effects of pH, contact time, amount of the adsorbent, initial concentration, and temperature on the adsorption of heavy metal ions were investigated. In the experimental study, the optimal pH values of Ni2+, Cu2+, and Cr6+in the CWH adsorption solution were 7.5, 6.0, and 5.0; the optimum contact times were 300, 180, and 120 min; and the optimum adsorbent dosages were 0.65, 0.50, and 0.40 g, respectively. The adsorption processes of Ni2+, Cu2+, and Cr6+by CWH are in accordance with the quasi-second-order kinetic model and Langmuir model, with the maximum adsorption capacity being 59.64, 77.98, and 96.89 mg/g, respectively. The thermodynamic model shows that it is an endothermic spontaneous process. Even after five adsorption–desorption cycles, the removal ratios of Ni2+, Cu2+, and Cr6+by CWH remained about 55.23, 65.63, and 71.46%, respectively. The structure of the water hyacinth before and after modification was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy. The results indicate that the surface of CWH was rough and the number of microporous increased and water hyacinth has been successfully carboxylated. The abovementioned results indicate that CWH can be used as an environmentally friendly and economical adsorbent.

A new, general copper-catalyzed oxidative tandem [4+2] cycloaddition of α-(N-arylamino) carbonyl compounds with aryl alkenes to produce highly substituted quinolines has been developed, which allows the formation of three new C–C bonds through a sequence of multiple C–H functionalizations, annulation, and [1,2]-aryl shifts.

A new anode strategy for accessing xanthen-9-azoles via an electrochemical C(sp3)–H/N–H cross-coupling of xanthenes with azoles is described. This reaction proceeds efficiently with a broad scope of both xanthenes and N–H-free azoles under metal- and additional oxidant-free conditions and represents a new access to direct incorporation of important N-heterocycle units into the resulting xanthenes.

A simple three-component 1,2-bromoesterification of alkenes with acids and N-bromosuccinimide under electrochemical oxidative conditions is described. This transformation enables the construction of β-bromoalkyl esters via oxidative C–Br/C–O difunctionalization, where a variety of alkenes, including styrenes and cycloolefins, were well tolerated to react efficiently with a wide range of acids, such as aromatic acids, aliphatic acids, and amino acids.

A new, one-step rhodium(III)-catalyzed annulation of 4-arylbut-3-yn-1-amines with internal alkynes through C–H functionalization is reported. This reaction allows the formation of three new chemical bonds, including two C–C bonds and one C–N band, thus selectively assembling various spiro[indene-1,2′-pyrrolidine]s with excellent functional group compatibility, high atom-economy, and step-efficiency.

A simple protocol for the three-component intermolecular alkylesterification of styrenes with toluenes and peroxyesters using a copper catalyst is described. A variety of ester-containing complex compounds were synthesized with excellent functional group tolerance and step efficiency. Employing the combination of carboxylic acids and di-tert-butyl peroxide (DTBP) oxidant instead of peroxyesters also gave similar results. In this transformation, aromatic acids, aliphatic acids, and amino acids were suitable substrates.

A novel cascade annulation of 1,7-diynes with water has been developed for the synthesis of furo[3,4-c]quinolin-4(5H)-one skeletons with high atom- and step-economy. The transformation was enabled by a palladium catalyst in the presence of copper salt as the promoter, involving the formation of one C–C bond and two C–O bonds. Moreover, the reaction exhibits good tolerance of functional groups and broad substrate scope. Notably, the control experiments support the incorporation of the new oxygen atom from water.

A new, three-component 1,2-alkylamination of styrenes with alkyl N-hydroxyphthalimide (NHP) esters and amines by Lewis acid and visible-light photoredox cooperative catalysis is described. This reaction employs alkyl NHP esters as general alkylation reagents to accomplish the 1,2-alkylamination of alkenes in high efficiency and with excellent functional groups tolerance, significantly enhancing the synthetic potential of 1,2-alkylaminations of alkenes for accessing complex functionalized amines.

Straightforward access to various substituted naphthalenones by copper-catalyzed [4 + 2] annulation cascades of 2-bromo-1-arylpropan-1-ones with terminal alkynes is presented. Employing a Cu(MeCN)4PF4catalyst and 1,10-phenanthroline (1,10-Phen) ligand enables the formation of three new C–C bonds in a single reaction via [4 + 2] annulation of a 2-bromo-1-arylpropan-1-one with an alkyne followed by α-alkylation with the other 2-bromo-1-arylpropan-1-one with excellent functional group tolerance and step efficiency.

In order to allow the user to quickly and accurately search the required information, a query optimization method based on a simulated annealing and particle swarm hybrid algorithm is proposed. The basic idea is: the query population into two flat sub populations, a sub population by using simulated annealing algorithm optimization, another sub populations by using particle swarm algorithm optimization, comparison of two adaptive values, to find the global optimal value. The experimental results show that the mixed algorithm, can further improve the precision and recall of query optimization.

This article introduces a vehicle license plate localization method which is based on gray image. This method mainly processes some uneven illumination and low-quality vehicle images. Firstly it uses edge detection operators to enhance images to plate region. Then it enhances with algorithm such as binaryzation, first-order points difference and median filtering in custom templates. And lastly it makes it more accurately in license plate localization through projection method enhancement. It is showed in experiments that this method can license plate localizes these kinds of low-quality license plate images accurately and effectively.

Keeping options open: The new and mild title reaction involving indoles selectively furnishes 1and 2with the aid of tert‐butyl hydroperoxide (TBHP). The method represents the first example of a copper‐catalyzed α arylation of α‐amino carbonyl substrates leading to α‐aryl α‐imino and α‐aryl α‐oxo carbonyl compounds using a CH oxidation strategy.

Imino oder Oxo: Die Titelreaktion unter Verwendung von tert‐Butylhydroperoxid (TBHP) überführt Indole selektiv und unter milden Bedingungen in die Produkte 1und 2. Es handelt sich um die erste kupferkatalysierte α‐Arylierung von α‐Aminocarbonyl‐Substraten zu α‐Aryl‐α‐imino‐ und α‐Aryl‐α‐oxocarbonyl‐Verbindungen über eine C‐H‐Oxidation.

A new, general method for the synthesis of phenanthridines has been developed by palladium‐catalyzed oxidative remote CH olefination–carboamination–CC bond cleavage tandem reaction. It is noteworthy that alkenes are used as the one‐carbon resources for this tandem reaction.

An efficient and resuble copper on iron catalyst has been prepared for the cleavage of the carbon‐carbon σ‐bond in α‐aminocarbonyl compounds leading to the corresponding formylamides and acids with a maximal TON of up to 51,000. It is noteworthy that the copper on iron catalyst can be easily separated from the reaction mixture, and retains its activity after several reuses.

A copper-catalyzed remote benzylic C–H functionalization strategy enabling 1,2-difunctionalization of alkenes with 2-methylbenzeneamides and nucleophiles, including alcohols, indoles, pyrroles, and the intrinsic amino groups, is reported, which is characterized by its redox-neutral conditions, exquisite site-selectivity, broad substrate scope, and wide utilizations of late-stage modifying bioactive molecules. This reaction proceeds through nitrogen-centered radical generation, hydrogen atom transfer, benzylic radical addition across the alkenes, single-electron oxidation, and carbocation electrophilic course cascades. While using external nucleophiles manipulates three-component alkene alkylalkoxylation and alkyl-heteroarylation with 2-methylbenzeneamides to access dialkyl ethers, 3-alkylindoles, and 3-alkylpyrroles, omitting the external nucleophiles results in two-component alkylamidation ([5+2] annulation) of alkenes with 2-methylbenzeneamides to benzo-[f][1,2]thiazepine 1,1-dioxides.

Ruthenium‐catalyzed intramolecular cyclization of an alkyne onto an α‐amido C(sp3) carbon atom proceeds smoothly under base‐free conditions to give quinolinones (II) and (IV) in moderate yields.

A new Pd‐catalyzed C—H bond activation‐annulation‐amination tandem method is presented for the synthesis of title compounds (III) and (V).

The new catalyst displays high activity (maximal TON of up to 51.000) and allows a large‐scale reaction (2.25 g substrate).

In most cases, high regio‐ and stereoselectivity is observed.

Indeno[1,2‐c]chromenes are formed if the substrates bear a terminal aryl group at the alkyne moiety.

The title reaction offers a mild and efficient method for the synthesis of 6H‐benzo[c]chromenes.

The atom‐economical and solvent‐free Conia‐ene route allows the selective construction of five‐ to six‐membered ring carbocycles from various linear β‐alkynic β‐keto esters and β‐alkynic β‐diketones.

The first example of the synthesis of indoline‐2,3‐diones using a transition‐metal‐catalyzed process is presented.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.