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Highly selective arylation catalyzed by palladium and directed by the acetamino group provides an efficient and practical protocol for constructing unique biaryl scaffolds, which could be further transformed into different structural units found in a range of natural products. 1 Introduction 2 Highly Regioselective Halogenation 3 Highly Regioselective Arylation 3.1 With Arylboronic Acids 3.2 With Trialkoxyarylsilanes 3.3 With Simple Arenes 3.4 Further Transformations 4 Conclusion [ABSTRACT FROM AUTHOR]

Abstract: A novel sulfonamide catalyst based on a room temperature ionic liquid (RTIL) has been developed for the enantioselective reduction of ketones in refluxing toluene. The optically active secondary alcohol products were obtained in good enantiomeric excess and excellent yields. The imidazolium-tagged sulfonamide catalyst can be readily recovered and reused four times without any significant loss of catalytic activity. [Copyright &y& Elsevier]

A novel metal-free oxidative carbonitration of alkenes by a nitration and C–H functionalization cascade process has been developed. This methodology provides an efficient way to construct valuable nitro-containing oxindoles. [ABSTRACT FROM AUTHOR]

A novel protocol for the preparation of various 3-alkylideneoxindoles viaa silver-catalyzed aromatic C–H functionalization has been developed. The process is simple, environmentally conscious, and avoids the use of abundant bases, oxidants, or other additives. [ABSTRACT FROM AUTHOR]

An oxidative homo dimerization of N-protected and free indole derivatives toward bioactive 3,3′-linked biindolyl scaffolds viaPd-catalyzed direct C–H transformations was first successfully demonstrated. [ABSTRACT FROM AUTHOR]

Optical properties of bismuth (Bi) film in function of temperature have been investigated by spectroscopic ellipsometry (SE). The solid-liquid phase transition point of Bi thin film is found to be ∼262 °C, lower than that of bulk Bi (271.3 °C). The interband transitions of solid Bi occur at 1.82, 3.02 and 4.00 eV, respectively, obtained from imaginary part of dielectric functions and absorption coefficient, which are also consistent with the fitting ellipsometric parameters of the oscillator center energies. A conspicuous difference of optical properties is revealed between solid and liquid Bi, whose characters are semimetal-like and metal-like, respectively. The free electron density of liquid Bi is 10 4 times higher than that of solid Bi. The optical properties of liquid Bi film are mainly influenced by free electrons instead of bound ones. However, with the temperature rising, the increase of both direct and indirect band gaps accords with the characteristics of semiconductor, which can be ascribed to the topological properties of Bi film. This work shows the unique advantage of SE on characterizing the optical properties of topological insulators. [ABSTRACT FROM AUTHOR]

An efficient metal-free tandem intramolecular oxidative C−H amination and iodization of phosphinamide was performed and a series of new phosphorus heterocyclic compounds was obtained. This method provides a concise and highly valuable pathway for the synthesis of difunctional atropoisomeric P-stereogenic phosphinamides. [ABSTRACT FROM AUTHOR]

We have developed a simple and effective method for the C-3 arylation of phosphorus-containing indole compounds in the presence of CuI under mild conditions. This reaction provides a reliable method for the modification of ligands. [ABSTRACT FROM AUTHOR]

A promoter‐free chalcogenophosphorylation reaction between diverse P(O)−H reagents and chalcogenosulfonates has been developed. In the absence of metal or any other additives, these transformations proceed through a spontaneous process at room temperature, which provide a convenient and compatible approach to a broad range of selenophosphates and thiophosphates. [ABSTRACT FROM AUTHOR]

A novel strategy of bisphosphorylation of anhydrides with P(O)–H reagents via a DMAP-catalyzed and DBU-promoted process has been developed. These one-step transformations proceed efficiently to provide convenient access to a variety of P–O–C–P motif containing organophosphorus compounds. In addition, the gram-scale synthesis and the efficient recovery of the by-product highlight the sustainability and applicability of this method. [ABSTRACT FROM AUTHOR]

To elucidate the biological mechanism of yellow rind formation on watermelon, the characteristics of soil bacterial community structure in rhizosphere and endophytic bacteria in stem of yellow rind watermelon were analyzed. Based on high-throughput sequencing technology, plant stem and rhizosphere soil samples, which collected from yellow and green rind watermelons were used in this paper, respectively. The structural characteristics of the endophytic bacteria in stems and soil bacterial communities in rhizospheres of yellow and green rind watermelons were comparative studied. Firstly, significant different proportions of some dominant bacteria and abundances could be detected between yellow and rind watermelons. Meanwhile, although different abundances of endophytic bacteria could be found, but no significant differences were observed between yellow and green rind watermelons. Moreover, Gemmatimonadota, Myxococcota, WPS-2, norank_f_Gemmatimonadaceae and Bradyrhizobium were the soil dominant bacterial genera in rhizosphere of green rind watermelon. All above results suggest that differences of rhizospheric and endophytic bacteria are exactly recruited as "workers" by different watermelon phenotypes relating to rind color formations. [ABSTRACT FROM AUTHOR]

A TFAA/DMSO/NaF‐based system for the efficient fluorination of P(O)−H and P(O)−OH compounds has been developed. Without adding highly toxic and expensive fluorination reagents, this novel transformation provides direct and compatible access to a variety of fluorophosphonates and phosphonofluoridates in a one‐pot manner. [ABSTRACT FROM AUTHOR]

N-Phosphorylated amides continue to be an unparalleled asset for the development of pharmaceutical molecules, and the importance of this framework has inspired researchers to look for concise and efficient methods for the synthesis of this unit. In this work, a new strategy was developed in which a one-pot synthesis of N-phosphorylated amides was achieved by a three-component reaction with carboxylic acids, phosphorus chlorides and azides under mild reaction conditions. To our knowledge, this is the first study in which this framework was constructed through a multicomponent reaction, which is innovative, efficient and economical. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed, temporary P(O) directing group assisted C–H bond arylation of carbazoles was achieved. The release of the directing group occurs spontaneously in the reaction and the mechanistic studies indicate that acid is essential for N–P bond cleavage. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed Catellani‐type reaction of indole with diethyl (iodomethyl)phosphonate has been developed. This new protocol provides an efficient and concise route to 2‐methylene phosphonate indoles, which are key synthons for the construction of indole alkaloids. [ABSTRACT FROM AUTHOR]

The low‐cost cobalt(II) catalyst has been used for the first time to achieve P(O)‐radical‐mediated bisfunctionalization of alkenes with diarylphosphine oxide and peroxides. This simple process is performed under mild conditions to afford a wide variety of phosphonation‐peroxidation products in a one‐pot manner. Computational studies are carried out to provide a theoretical support for the P(O)‐radical‐involved bisfunctionalization of alkenes. [ABSTRACT FROM AUTHOR]

A novel type of oxime phosphonate was synthesized and used in the intermolecular cascade radical addition reaction of alkenes to access β-aminophosphonates via visible-light-driven N-centered iminyl radical-mediated and redox-neutral selective C–P single-bond cleavage in an active phosphorus radical route. The procedure is characterized by its ability to achieve the construction of Csp3–P and Csp3–N bonds without the requirement for oxidants and bases. [ABSTRACT FROM AUTHOR]

Highlights • A significant dispersion of penetration depth with Bi 0.38 Se 0.62 films versus phonon energy was found. • A dispersive plasma energy was introduced to traditional MDF model for modelling topological insulators. • Spectroscopic ellipsometry was shown to be a useful tool for characterizing the properties of the topological insulators. Abstract Optical properties evolution of Bi 1- x Se x films with different compositions were investigated by spectroscopic ellipsometry (SE). A significant dispersion of penetration depth of Bi 0.38 Se 0.62 films was observed, which would lead to a varying carrier concentration with the different wavelength because of the topologically protected surface state. To describe the special properties of topological insulators, dispersive plasma energy was introduced into traditional dielectric function model. Optical properties of Bi 0.38 Se 0.62 film were acquired by this modified model and the topologically protected surface state could be represented from the dispersion properties of free carrier concentration with the smaller plasma energy versus the deeper penetration depth. We demonstrated that SE is a useful tool for characterizing the properties of the topological insulators. [ABSTRACT FROM AUTHOR]

A Cerium(IV)‐promoted phosphinoylation‐nitratation of alkenes is established under mild conditions. In this process, Ceric ammonium nitrate (CAN) acts as a cheap phosphorus‐radical initiator, as well as a nitrate donor. Various β‐nitrooxyphosphonates are delivered in high yield in a one‐pot manner. [ABSTRACT FROM AUTHOR]

A new type of phosphine radical precursor for C—P bond formation has been developed and successfully used in visible‐light‐catalyzed phosphonation‐annulation of unsaturated sulfonamides and carboxylic acids. The catalytic process is simple and green accessible, and no additional oxidant or base is needed. Mechanistic studies suggest that the reaction proceeds via a single electron transfer pathway. A new type of phosphine radical precursor for C—P bond formation has been developed and successfully used in visible‐light‐catalyzed phosphonation‐annulation of unsaturated sulfonamides and carboxylic acids. The catalytic process is simple and green accessible, and no additional oxidant or base is needed. Mechanistic studies suggest that the reaction proceeds via a single electron transfer pathway. [ABSTRACT FROM AUTHOR]

Abstract Thin films of silicon nanocrystals embedded in SiO 2 matrices were prepared by annealing a photoresist of hydrogen silsesquioxane. As compared to films made by a common method of annealing SiO x (1 < x < 2), significant enhancement on photoluminescence intensity was observed. Spectroscopic ellipsometry was applied to figure out optical properties of nc-Si made from HSQ. High-resolution tunneling electron microscopy, photoluminescence and absorption spectra were taken to either confirm the fitting results of SE or characterize structural, morphological and photoluminescent properties of all samples. The deduced refractive indices of nc-Si:SiO 2 films made from HSQ were given. The influence of particle size and spatial distribution of nc-Si on the extinction coefficient K and PL spectra was observed and discussed. Highlights • Photoluminescence of Si nanocrystals prepared by HSQ enhanced significantly. • SE measurement figured out optical properties of Si nanocrystals made from HSQ. • HSQ is a promising material to realize all-silicon light sources. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and practical method for the synthesis of α,α‐difluoro‐γ‐aminophosphonates through photocatalyzed intermolecular aminodifluoromethylphosphonation of alkenes has been developed. In this reaction, difluoromethylphosphonate is used as an important fluorinated reagent. Furthermore, the mild reaction conditions, simple operation, and broad substrate scope make this protocol very practical and attractive. The derivatization reaction in the synthesis of difluoromethylphosphonated chiral binaphthylamine ligands and α,α‐difluoro‐γ‐aminophosphoric acid highlight the applicability of this method. [ABSTRACT FROM AUTHOR]

Light transmission at the Au/air interface was measured for wedge-shaped Au film samples. Light refraction continuously changing its sign from positive to negative at the Au/air interface in the spectrum range of 470–700 nm was observed with a zero refraction occurred at about 525 nm. The results indicate that the effective refraction index n e of samples are not correlated with wedge angles, implying that n e can be considered an intrinsic characteristic of the metal material. The positive and negative refractions observed in the experiment can be attributed to the dispersive feature of the dielectric function of Au with qualitative explanation according to the mechanisms of electron transition and the boundary conditions restricted at the interface. [ABSTRACT FROM AUTHOR]

A Rh/Ni-catalyzed cascade sequence of allylamine isomerization and hydrophosphonylation to synthesize α-aminophosphonates has been disclosed. The reaction, which not only allows the generation of widespread valuable α-aminophosphonates under simple systems and mild conditions, but also enriches the process of olefin isomerization–addition both in catalytic systems and various reaction types. [ABSTRACT FROM AUTHOR]

• Spirocyclization via dearomatization of tryptamine derivatives. • Three-component tandem reaction to form C C and C N bond formation. • Easily handled and broadly available formic acid as C1 feedstock. • Commercially available and cost effective organocatalyst. A reductive spirocyclization of tryptamine derivatives with formic acid as a C1 building block has been achieved via dearomatization. The reaction was catalyzed by a commercially available and cost-effective organic base, tetramethylguanidine (TMG). A variety of spiroindolenines were obtained in high yields under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: A novel arylnitration of alkenes by nitration and C–H functionalization cascade process has been developed. This methodology provides an efficient way to construct a variety of nitro-containing oxindoles and dihydroquinolin-2(1H)-ones. In addition, the process exhibits significant functional group tolerance. Moreover, the use of inexpensive and readily available starting materials makes this practical and atom-economical approach particularly attractive. [Copyright &y& Elsevier]

Abstract: A novel metal-free oxidative arylphosphination of activated N-substituted-N-arylacrylamide derivatives by phosphorylation and C–H functionalization cascade process has been developed. This methodology provides an efficient way to construct a variety of phosphorus-containing oxindole moieties. [Copyright &y& Elsevier]

Abstract: A new method for the synthesis of tricyclic 2,3-dihydro-4-quinolones by the NiCl2(PMe3)2-catalyzed carboamination of alkenes by intermolecular decarboxylative cycloaddition reaction is reported here. Isatoic anhydrides were reacted with various norbornenes to afford the novel structure of quinolones. This protocol is simple and easy to handle. [Copyright &y& Elsevier]

Abstract: A new protocol for the synthesis of polysubstituted isocoumarins from 2-iodobenzoic acid and β-diketone compounds has been developed. The occurrence of C-arylation cyclization reaction in transition-metal-free systems and ortho-induced substrates has been exploited. Reactions using these inexpensive conditions have displayed high functional group tolerance and excellent yields. [Copyright &y& Elsevier]

Abstract: By using Tf2O as a catalyst, we have developed a protocol for the preparation of various dibenzo[a,d]cycloheptene cores via Friedel–Crafts alkylation. Using this method as the key step, we also present concise and useful routes to synthesize the natural products Diptoindonesin D, Pauciflorial F, and (±)-Ampelopsin B. Notably, this process exhibited following very attractive features: (i) the process is metal free, with only catalytic amounts of Tf2O being employed, and (ii) the process is simple and environmentally conscious, avoiding the use of excess amounts of base, oxidant, or other additives. [Copyright &y& Elsevier]

A novel metal-free oxidative carbonitration of alkenes by a nitration and C–H functionalization cascade process has been developed. This methodology provides an efficient way to construct valuable nitro-containing oxindoles. [ABSTRACT FROM AUTHOR]