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The oxidative dimerization of 2-phenylpyridine derivatives using cobalt catalysis is reported. Three types of reaction conditions were developed with different loadings of cobalt catalyst. Cross coupling of two different 2-arylpyridines using cobalt catalysis proceeded with modest yields and selectivity.

A Pd/norbornene/Cu cooperative catalysis for the efficient synthesis of 2-(arylthio)aryl ketones from aryl halides and thioesters has been developed. The first example of cooperative catalysis by palladium, norbornene, and copper, wherein the C(O)-S bond of thioesters is cleaved by a Pd(II) palladacycle with the assistance of CuI, has been observed.

Ligand-free CuI-catalyzed bis(pinacolato)diboron (B2(pin)2) conjugate addition and reduction onto α,β-unsaturated carbonyl compounds in moderate to excellent yields has been demonstrated.

A facile and efficient annulation of 2-aminobenzamides and tert-butyl nitrite was developed, affording 1,2,3-benzotriazine-4-(3H)-ones in good yields under mild conditions. Notably, the reaction was carried out in the absence of strong acid and tert-butyl nitrite was employed as the nitrogen source.

A facile and practical synthetic route of unsymmetrical 1,3-diynes via the PdCl/CuI catalyzed oxidative coupling of two different terminal alkynes has been developed by using 3-(diphenylphosphino)propanoic acid as a ligand in the presence of oxygen. This system is suitable for not only aromatic alkynes but also heteroaromatic and aliphatic alkynes which were transformed into the corresponding unsymmetrical 1,3-diynes in moderate to good yields at room temperature. Moreover, the unsymmetrical 1,3-diynes were also obtained on a multi-gram scale. Mechanistic studies suggest that oxygen plays a key role in the catalytic cycles.

Three rare carbamate-containing alkaloids, penicimutamides A–C (1–3), were isolated from a fungal mutant from the diethyl sulfate (DES) mutagenesis of marine-derived Penicillium purpurogenum G59. Their structures, including their absolute configurations, were determined by spectroscopic methods, especially the X-ray crystallography and CD analyses. HPLC-UV and HPLC-MS analyses evidenced that 1–3 were only produced in the mutant strain via biosynthetic pathways that were silent in the parental strain and activated by DES mutagenesis.

In this paper, we report an efficient one-pot synthesis of 1,2,3-triazole/quinoline-fused imidazo[1,2-a]pyridines starting from 2-(2-bromophenyl)imidazo[1,2-a]pyridines, alkynes, and sodium azide. This novel method involves a one-pot bimetallic relay-catalyzed cascade process combining azide–alkyne cycloaddition, C–N coupling between 1,2,3-triazole and aryl bromide, and intramolecular cross dehydrogenative C–C coupling between 1,2,3-triazole and imidazo[1,2-a]pyridine. Notable features of this protocol include simple starting materials, sustainable oxidants, reduced synthetic steps, and high efficiency.

An efficient transition-metal-free fluoroarylation reaction of N-aryl diazoacetamides with NFSI (N-fluorobenzenesulfonimide) is described. This reaction directly provides 3-fluorooxindole derivatives in yields of 67–93% with high selectivity via a carbene-free process under mild reaction conditions.

A series of indolyl substituted 1,4,6,7-tetrahydropyrano[4,3-c]pyrazole derivatives were synthesized via a domino method based on the 1,4:3,6-Dianhydrofructose. The mechanism was proposed and proved by calculation with a density functional theory (DFT), which includes formation of phenylhydrazone, furanone ring opening, Fischer indole synthesis, pyrazole ring closing and a furan ring expansion. In vitro antitumor activity of all synthesized compounds against four human cancer cell lines (MCF-7, EC-109, HGC-27, and PC-3 cell lines) were then evaluated, using MTT assay. We found that most of the compounds were more potent than the positive control 5-fluorouracil. Particularly, compound 4i against HGC-27 and PC-3, 4j against EC-109 cell lines showed three fold greater activity than 5-fluorouracil, respectively. The activity of compounds 4c and 4d against MCF-7 cell line was close to that of doxorubicin.

Rare-earth-metal complexes stabilized by amine-bridged tri(phenolato) ligands were developed, and their activities in catalyzing transformations of CO2 were studied. A series of terminal epoxides and challenging disubstituted epoxides were converted into the respective cyclic carbonates in the presence of CO2 in yields of 58 to 96 %. In addition, these rare-earth-metal complexes also showed good activities in catalyzing three-component reactions of anilines, epoxides, and CO2, which generated 5-substituted-3-aryl-2-oxazolidines in yields of 48 to 96 %, as a useful strategy to construct oxazolidinones.

Asperethers A–E (1–5), five new 20-nor-isopimarane diterpenoids having a 14,16-cyclic ether unit and possessing a unique 6/6/6/5 tetracyclic skeleton, which had not so far been described for this class of diterpenoids, were identified from the culture extract of Aspergillus wentii SD-310, a fungus obtained from a deep-sea sediment sample. The structures of these compounds were established on the basis of detailed interpretation of NMR and mass spectroscopic data, and their relative and absolute configurations were confirmed by NOESY data and X-ray crystallographic analysis, as well as by TDDFT calculations of their ECD spectra. Compounds 1–5 showed cytotoxic activities against several tumor cell lines.

A three-component reaction of isatin, 3-methyl-1-phenyl-1H-pyrazol-5-amine, and piperidine-2,4-dione was treated in ionic liquids catalyzed by TsOH and provided an efficient and green method for the synthesis of spiro[indoline-3,4′-pyrazolo[3, 4-b][1,6]naphthyridine]-2,5′(1′H)-dione derivatives in high yields.

The first catalytic asymmetric aminotrifluoromethylation of alkenes by using Togni′s reagent (II) has been developed.

We have developed an environmentally benign and practical protocol for the synthesis of pyrrolo[1,2- a ]quinoxalines, which represent ubiquitous structural units common to a number of biologically active compounds. This synthetic system features simple operation and using clean oxidant, as well as mild reaction conditions. Both aromatic and aliphatic aldehydes can be used for the reaction and the products were obtained in good to excellent yields.

2-Alkoxy-2,3-dihydrofurans were found to be versatile benzannulation reagents. Indoles can be synthesized in good to excellent yields via the [4+2] annulation of 2-butoxy-2,3-dihydrofuran with pyrroles catalyzed by copper bromide. With the same protocol, carbazoles can also be obtained when indoles are used as starting material with the aid of p-toluenesulfonic acid. This type of benzannulation reagent can also be used to synthesize benzofuran, benzothiophene and naphthalene derivatives in the presence of a catalytic amount of triflic acid in moderate yields. This benzannulation protocol features wide substrate scope and mild reaction condition. Moreover, most of examples have a good regioslectivity.

Bioprobes based on fluorogens with aggregation-induced emission (AIE) characteristics have been increasingly used in chemosensing and bioimaging due to their high sensitivity, photostability and biocompatibility. In this review, we summarize the design of cellular organelle specific (cytoplasm membrane, mitochondria, lysosomes, lipid droplets and nucleus) AIE bioprobes and their applications in organelle imaging, organelle bioactivity monitoring, and image-guided cancer cell ablation.

The introduced protocol has the advantages of readily available starting materials, short reaction times, and good regioselectivity.

Metal-organic frameworks (MOFs), also known as coordination polymers, represent an interesting type of solid crystalline materials that can be straightforwardly self-assembled through the coordination of metal ions/clusters with organic linkers. Owing to the modular nature and mild conditions of MOF synthesis, the porosities of MOF materials can be systematically tuned by judicious selection of molecular building blocks, and a variety of functional sites/groups can be introduced into metal ions/clusters, organic linkers, or pore spaces through pre-designing or post-synthetic approaches. These unique advantages enable MOFs to be used as a highly versatile and tunable platform for exploring multifunctional MOF materials. Here, the bright potential of MOF materials as emerging multifunctional materials is highlighted in some of the most important applications for gas storage and separation, optical, electric and magnetic materials, chemical sensing, catalysis, and biomedicine.

A highly enantioselective rhodium-catalyzed arylation of benzoxazinones and quinoxalinones with arylboroxines was realized for the first time by employing a simple sulfur-olefin as the ligand. This protocol provides an efficient access to chiral 3,4-dihydrobenzo[1,4]oxazin-2-ones and dihydroquinoxalinones with exceptionally high enantiomeric purity (up to 99.9% ee).

A synthetically useful transformation arises from NBS-mediated dinitrogen extrusion of N-aryl diazoacetamides under catalyst-free conditions, which gives 3-bromooxindoles in high to excellent yields with high selectivity via a non-carbene process.

Pd-catalyzed regioselective coupling of γ-C(sp3)–H bonds of oxalyl amide-protected amino acids with heteroaryl and aryl iodides is reported. A wide variety of iodides are tolerated, giving the corresponding products in moderate to good yields. Various oxalyl amide-protected amino acids were compatible in this C–H transformation, thus representing a practical method for constructing non-natural amino acid derivatives.

Neopeapyran ( 1 ), an unusual furo[2,3 b ]pyran analogue, together with a new cyclopeptide, turnagainolide C ( 2 ), were isolated from Streptomyces sp. S2236 associated with the rhizosphere soil of Panax notoginseng . The planar structure and relative configuration of neopeapyran ( 1 ) were elucidated on the basis of spectroscopic techniques, while the absolute configuration was determined by TDDFT calculation. The absolute configuration of turnagainolide C ( 2 ) was determined by partial hydrolysis, together with the advanced Marfey's method and spectroscopic analysis. The antimicrobial activities of these two compounds were also investigated.

Two new N -methyladenine-containing diterpenes, nemoechines F ( 1 ) and G ( 2 ), were isolated from the South China Sea sponge Agelas aff. nemoechinata . The structures were assigned on the basis of spectroscopic date. Compound 2 showed weak activity against Jurkat cell lines with IC 50 of 17.1 μmol/L.

Naturally occurring amino acids taurine and homotaurine are immobilized on hybrid silica and fully characterized.

10 Title compounds of type (III) are prepared, and their fluorescence emission wavelength in methanol is measured.

A general and practical method for the preparation of trans-2-substituted-4-halopiperidines and cis-2-substituted-4-halotetrahydropyrans is reported. Using 5 mol % of AlCl3 as the catalyst and 2 equiv of trimethylsilyl halides as the halide sources, aza-Prins cyclization of N-tosyl homoallylamine or Prins cyclization of homoallylic alcohol with carbonyl compounds could be readily realized, giving the corresponding trans-2-substituted-4-halopiperidines or cis-2-substituted-4-halotetrahydropyrans in high yields and satisfactory diastereoselectivity.

The first asymmetric synthesis of spiro-γ-lactam oxindoles bearing three stereocenters is reported. One-pot thiol-Michael/Mannich/lactamization reactions promoted by a recyclable fluorous bifunctional cinchona alkaloid/thiourea organocatalyst afford products in moderate to good yields with up to 95% ee and 6:1 dr.

A novel rhodium-catalyzed/copper-mediated C2-selective C−H alkynylation of indoles using γ-substituted tert-propargyl alcohols as the alkynylating reagent and a removable 6-methylpyridin-2-yl as the directing group has been developed, which provides a viable pathway for direct C2-selective alkynylation of indoles. Moreover, this strategy could be extended to the C−H alkynylation of carbazoles at the C1 position.

Ni(II)-catalyzed C–H arylation using Ar2I+X− or ArX as the arylating reagent via oxidative addition has been well investigated. However, the analogous cross-coupling of C–H bonds with organoboron reagents via transmetallation remains a great challenge. Here we report the first Ni(II)-catalyzed direct C–H arylation with arylboronic acid esters assisted by a removable bidentate auxiliary. This procedure is scalable and compatible with a wide range of functional groups, providing a complementary protocol for the synthesis of biaryl compounds.

Review: recent breakthroughs in SN2-type nucleophilic fluorination reactions using alkali metal fluorides promoted by protic solvents; 50 refs.

Lithium-ion batteries (LIBs) are attractive candidates as power sources for various applications, such as electric vehicles and large-scale energy storage devices. However, safety and life issues are still great challenges for the practical applications of LIBs. Metallic lithium plating on the negative electrode under critical charging conditions accelerates performance degradation and poses safety hazards for LIBs. Therefore, anode lithium plating in LIBs has recently drawn increased attention. This article reviews the recent research and progress regarding anode lithium plating of LIBs. Firstly, the adverse effects of anode lithium plating on the electrochemical performance of LIBs are presented. Various in situ and ex situ techniques for characterizing and detecting anode lithium plating are then summarized. Also, this review discusses the influencing factors that induce anode lithium plating and approaches to mitigating or preventing anode lithium plating. Finally, remaining challenges and future developments related to anode lithium plating are proposed in the conclusion.

An organocatalytic formal [4 + 2] cycloaddition reaction has been realized that permits rapid access to a wide range of bicyclo[2.2.1]heptane-1-carboxylates in a highly enantioselective manner from simple starting materials under mild and operationally simple conditions.

An electrochemical method for the decarboxylative coupling of α-keto acids with ortho-phenylenediamines was developed. The reaction proceeded smoothly in aqueous solution under air and metal catalyst-free conditions to afford 2-substituted benzimidazoles in good yields. Benzothiazoles could also be synthesized by this protocol.

The scalable title reaction offers access to various 3,4-dihydroisoquinoline derivatives in high yields.

This paper summarizes our recent progress on the preparations and applications of electropolymerized thin films of redox-active ruthenium complexes. Thin films of vinyl-functionalized diruthenium or ruthenium-amine conjugated complexes are prepared by reductive electropolymerization. The resulting films are useful for multistate near-infrared electrochromism, ion sensing, and mimicking flip-flop and flip-flap-flop logic gates. The oxidative electropolymerization of diruthenium complexes with two distal triarylamine units affords electropolymers with an alternating diruthenium and tetraphenylbenzidine structural unit. The applications of the resulting films in multistate near-infrared electrochromism and resistive memory are discussed.

A copper(I)-catalyzed tandem reaction of 2-iodoanilines with isothiocyanates was achieved in hydrophobic [bmim][PF6] ionic liquid under mild conditions, generating a variety of 2-aminobenzothiazoles in good to excellent yields. The tandem reaction that was carried out in [bmim][PF6] has some obvious advantages such as accelerated reaction rate and increased yield as compared with the reaction run in volatile solvents such as toluene. Furthermore, the CuI/1,10-phenanthroline catalytic system can be reused up to eight times without loss of activity and efficiency. Copyright © 2016 John Wiley & Sons, Ltd.

Four different types of TEMPO derivatives incorporated with an ionic liquid moiety and N,N-bidentate coordination group (IL–TEMPO-N,N) were prepared. The CuBr/IL–TEMPO-N,N system showed high catalytic activity toward the synthesis of aldehydes and imines via the aerobic oxidation of alcohols in 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4). Both the Cu catalyst and IL–TEMPO-N,N co-catalyst in homogeneous catalytic systems could simultaneously be recovered from the products by extraction using Et2O. The remaining catalyst system in the ionic liquid phase could be reused for several cycles without obvious loss of catalytic activity. Protocols for highly efficient and recyclable aerobic oxidation of alcohols to aldehydes and imines were established.

Six new (2, 4–8) and two known polyketides with a basic structure of an anthraquinone-xanthone were isolated from mycelia and culture broth of the fungus Engyodontium album strain LF069. The structures and relative configurations of these compounds were established by spectroscopic means, and their absolute configurations were defined mainly by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Compounds 2 and 4–8 were given the trivial names engyodontochone A (2) and B–F (4–8). Compounds 5–8 represent the first example of a 23,28 seco-beticolin carbon skeleton. The relative and absolute configurations of two known substances JBIR-97/98 (1) and JBIR-99 (3) were determined for the first time. All isolated compounds were subjected to bioactivity assays. Compounds 1–4 exhibited inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA) that was 10-fold stronger than chloramphenicol.

An asymmetric synthesis of N-aryl sulfinamides was achieved through copper-catalyzed coupling reactions of aryl iodides with sulfinamides. Such a kinetic resolution process provided the desired coupling products in moderate to good yields and with moderate enantioselectivities.

Carbazole preferentially reacts with the fluorine group of fluorinated iodoarenes to form iodinated N-arylcarbazole intermediates.

A copper-catalyzed intramolecular amidation of unactivated C(sp(3) )-H bonds to construct indoline derivatives has been developed. Such an amidation proceeded well at primary C-H bonds preferred to secondary C-H bonds. The transformation owned a broad substrate scope. The corresponding indolines were obtained in good to excellent yields. N-Formal and other carbonyl groups were suitable and were easily deprotected and transformed into methyl or long-chained alkyl groups. Preliminary mechanistic studies suggested a radical pathway.

Silver-mediated direct trifluoromethoxylation of α-diazo esters and ketosteroid was disclosed. The reactions of alkyl α-diazo arylacetates with AgOCF3 or CF3SO2OCF3/AgF at −30 to 10 °C under a N2 atmosphere provided α-trifluoromethoxyl arylacetates in up to 90% yield, while alkyl α-diazo vinylacetates reacting with CF3SO2OCF3/AgF or AgOCF3 afforded γ-trifluoromethoxyl α,β-unsaturated esters in up to 94% yield. The α-diazo ketosteroid was also trifluoromethoxylated under the standard reaction conditions. This protocol allows for an effective and convenient access to a large number of synthetic building blocks, which are promising in the development of new functional OCF3-molecules.

The transition-metal-catalyzed direct triflation of naphthyl amides and naphthyl ketones has been accomplished for the first time. Benzophenone (BP) was found to be a suitable ligand for the cross-coupling reactions. Density functional theory (DFT) calculations revealed that excessive amounts of HOTf inhibit the reductive elimination of the C–F bond to realize the unusual reductive elimination of the C–OTf bond.

The Pd-catalyzed synthesis of benzylboronic esters through coupling of aryl triflates with 1,1-diborylalkane under ambient conditions is described. Varieties of primary and secondary arylboronic esters could be successfully synthesized by this strategy. Competitive reaction demonstrated that aryl C–OTf bond was more inert than aryl bromide.

A Friedel-Crafts alkylation reaction of styrenes with trifluoropyruvates has been developed, which delivered allylic alcohols in excellent yields (up to 98%) using the Ni(ClO4)2·6H2O/bipyridine complex as a catalyst. The asymmetric reaction was catalyzed by the chiral Cu(OTf)2/bisoxazoline complex to afford the corresponding chiral allylic alcohols bearing trifluoromethylated quaternary stereogenic centers in moderate enantioselectivities (up to 75% ee).