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We herein report an efficient approach for the assembly of multiply substituted imidazoles and oxazoles in a single-step manner. These transformations are based on a decarboxylation addition and annulation of readily accessible aromatic carboxylic acids and aliphatic nitriles and exhibit good functional group compatibility and a high step economy. The reaction is scalable, and as-prepared products could be transformed into practical skeletons. Importantly, the late-stage derivatization of Momelotinib highlights the potential utility of this methodology.

In this study, the biomechanical differences among three internal fixation configurations for treatment of Pauwels type II and III femoral neck fractures were analyzed. Using finite element analysis, the femur displacement and stress distributions of the internal fixation device and fracture section were obtained for different patients and movement conditions. The results show that patients with osteoporosis are more prone to femoral varus and femoral neck shortening, and the fracture probability of the device for these patients is higher than that for patients with normal bone. The treatment effect of the inverted-triangle screw (ITS) fixation and proximal femoral nail anti-rotation (PFNA) fixation is better than that of dynamic hip screw (DHS) fixation. The ITS fixation is more suitable for the treatment of the normal bone patients with Pauwels II femur neck fracture. However, the PFNA fixation has better biomechanical advantages and better capability for anti-femoral neck shortening. Therefore, it is suitable for the treatment of femoral neck fracture patients with osteoporosis.

With environmental and resource issues become increasingly prominent, as well as the requirements of the bioeconomy, the synthesis of polyurethane tends to follow the green chemistry and uses sustainable biological resources as raw materials. As a kind of biomass material, sorbitol has great potential for the bio-based polyurethane industry because of the high performance that sorbitol brings to polyurethane. What,s more, the various extraction technologies for sorbitol have matured. This paper reviews the extraction methods of sorbitol and analyzes the effects of sorbitol as polyols, crosslinkers and chain extenders used in polyurethane. Sorbitol based non-isocyanate polyurethane was also introduced.

The three-component tandem reaction of 2-aminobenzonitriles, arylboronic acids and ketones allowing the synthesis of polysubstitution quinolines is reported. This strategy presents a practical, efficient, one-pot procedure that delivers functional quinolines in moderate to good yields with high functional group tolerance. To enrich the synthetic applications in accessing diverse quinolines, a new method for the introduction of halogen substituents into target products has been developed as well, which shows potential for further synthetic elaborations.

A nickel-catalyzed strategy for the synthesis of 1,3-diaryl-6H-pyrazino[2,1-b]quinazolin-6-one was developed. This method enabled us to access valuable pyrazino-fused quinazolinones with tolerance of many functional groups even at room temperature. The desired pyrazino-fused quinazolinones emit strongly in both solution and solid states. Furthermore, the thermally-activated delayed fluorescence (TADF) of 3a was investigated. This study provides an efficient synthetic route for the development of TADF-active pyrazino-fused quinazolinones, thus expanding the application range of this versatile molecular scaffold in optoelectronics.

An efficient and straightforward protocol for the assembly of the pharmaceutically and biologically valuable oxazole skeleton is achieved for the first time from readily available simple arenes and functionalized aliphatic nitriles. This transformation involves palladium-catalyzed C-H activation, carbopalladation and a tandem annulation sequence in one pot. Notably, the reaction proceeds efficiently under redox-neutral conditions, and exhibits high atom-economy. Deuterium-labeling experiments suggested that C-H bond cleavage of the simple arenes might be the rate-determining step.

Heterocycle-fused quinazolinone derivatives have attracted great attention due to their diversified biological and optical activities. In this study, a novel one-pot palladium-catalyzed cascade C–C coupling/cyclization/aromatization of 2-(4-oxoquinazolin-3(4H)-yl)acetonitrile derivatives with arylboronic acids has been disclosed to synthesize 1,3-diaryl-6H-pyrazino[2,1-b]quinazolin-6-one in water. This protocol provides an efficient access to valuable pyrazino-fused quinazolinones in a green solvent (i.e., water) with yields ranging from moderate to excellent. Furthermore, the photophysical properties of these molecules were investigated. The resultant pyrazino-fused quinazolinones exhibit tunable fluorescence, and 3e displays the aggregation induced emission properties with a large Stokes shift. This study provides a useful approach to the development of pyrazino-fused quinazolinones, which have potential applications in chemistry, biology, and materials science.

The homoleptic lanthanide complex Sm[N(TMS)2]3 is an efficient rare-earth catalyst for the hydroboration of alkynes to the corresponding alkenylboron compounds. Practical applications were demonstrated through a gram-scale synthesis and further transformations of an alkenylboron ester to a series of functional compounds. Isotopic labeling experiments, 1H NMR monitoring and kinetic studies were conducted to elucidate the reaction mechanism.

Complete solid solutions between LaTaON2 and SrZrO3, i.e. (LaTaON2)1−x(SrZrO3)x (0 ≤ x ≤ 1) have been built which are very useful in tailoring many important parameters of LaTaON2. Band gap of LaTaON2 becomes tunable by controlling the level of solid solutions with SrZrO3. Structural distortions, defects (e.g. Ta4+ species) concentration and surface hydrophilicity of LaTaON2 are largely improved by introducing SrZrO3 in the structure. These modifications contribute to much enhanced photocatalytic activities of solid solutions for oxygen production which clearly outperform pristine LaTaON2 under visible light illumination. Apparent quantum efficiency as high as 0.87% at 420 ± 20 nm was achieved at (LaTaON2)0.6(SrZrO3)0.4 (x = 0.4). Further analysis suggest that introducing SrZrO3 results in realignment of band edge positions of LaTaON2 so as to be more appropriate for water splitting reactions.

A novel palladium-catalyzed protocol for the synthesis of 9-arylacridines via tandem reaction of 2-(arylamino)benzonitrile with arylboronic acids in water has been developed with good functional group tolerance. The present synthetic route could be readily scaled up to gram quantity without difficulty. This methodology was further extended to the synthesis of a 4'-OH derivative, which showed estrogenic biological activity. Preliminary mechanistic experiments showed that this transformation involves a nucleophilic addition of aryl palladium species to the nitrile to generate an aryl ketone intermediate followed by an intramolecular Friedel-Crafts acylation and dehydration to acridines.

A palladium-catalyzed carbon-carbon bond activation-initiated reaction of 2-(3-phenyloxiran-2-yl)benzonitriles with arylboronic acids is reported. Multiple chemical bonds were cleavaged and reconstructed via β-carbon elimination in this reaction, enabling the construction of valuable benzo-fused dipyrromethenes that are difficult to prepare by other methods. Additionally, a series of benzannulated boron dipyrromethenes are synthesized and show practical significance in terms of expanding the applications and types of fluorescent materials. The proposed mechanism is supported by preliminary mechanistic experiments.

This study presents the first example of the Pd-catalyzed cascade reactions of 5-oxohexanenitrile with arylboronic acids, affording important synthon 2-methylpyridines that can be further translated through C(sp

The efficient selective synthesis of furans and pyrroles has been realized by means of a palladium-catalyzed tandem addition/ring-opening/cyclization reaction of 2-(3-aryloxiran-2-yl)acetonitriles with arylboronic acids in aqueous medium for the first time. The chemoselectivity of this transformation can be predominantly governed by the steric effects of arylboronic acids: the reactions of 2-(3-aryloxiran-2-yl)acetonitriles with the less sterically hindered arylboronic acids provided furans as the sole products, while those of the sterically bulky arylboronic acids delivered pyrroles selectively. The 18O-labelled experiments revealed that the oxygen atom of furans is derived from water, and a plausible mechanism for this selective synthesis of furans and pyrroles was proposed.

We have demonstrated the first ever example of nickel complexes as effective catalysts to promote the C–C, N–C cascade coupling of ketonitriles with arylboronic acids, affording potentially biologically active 3-carboxylate-2,5-diaryl-pyrroles as well as 2,5-diarylpyrroles and 2,6-diarylpyridines. This protocol features a broad scope of substrates and excellent functional group tolerance, thus representing a highly versatile and atom-economical alternative to novel methods for the synthesis of various unsymmetrical diarylpyrroles and diarylpyridines under manageable conditions.

A Pd-catalyzed tandem reaction of 2-(cyanomethoxy)chalcones with thiophenes through direct C–H addition and sequential intramolecular conjugate addition/cyclization/aromatization provides a diverse range of 3-aryl-1-(thiophen-2-yl)benzofuro[2,3-c]pyridines. A representative product was assessed as a ratiometric fluorescent probe for Hg2+. This chemistry could also be applied to the synthesis of other fused ring systems.

Ge-Modified GaN–ZnO wurtzite solid solutions have been synthesized via moisture-assisted high temperature ammonolysis with very high Zn content (Zn/(Zn + Ga + Ge) > 0.61). A new intermediate, Zn2GeO4, has been identified during the synthesis, which breaks the limit imposed by the ZnGa2O4 intermediate on the Zn content. AQE as high as 10.8% at 420 ± 20 nm has been achieved for H2 liberation from water.

The selective catalytic reduction of amides to value-added amine products is a desirable but challenging transformation. Here, we present a combined KOtBu/BEt3 catalyst for the deoxygenative reduction of tertiary, secondary, and even notoriously challenging primary carboxamides with pinacolborane (HBpin) at 25–60 °C. This novel transition-metal-free methodology is readily applicable to the synthesis of drug molecules.

Lithium-promoted hydroboration of alkynes and alkenes using commercially available hexamethyldisilazane lithium as a precatalyst and HBpin as a hydride source has been developed. This method will be appealing for organic synthesis because of its remarkable substrate tolerance and good yields. Mechanistic studies revealed that the hydroboration proceeds through the in situ-formed BH

A new method for converting easy availability starting materials 2-(2-oxoindolin-3-yl)acetonitrile, arylboronic acids, and alcohols into 2-arylquinoline-4-carboxylates is reported. The procedure involves a three-component addition/ring expansion/esterification reaction in the presence of Pd(II) catalyst with high functional group tolerance under mild conditions. In addition, the photophysical properties of the resulting product were investigated and exhibited excellent polarity-sensitive fluorescence properties and AIE property.

Electrospinning is a unique method to prepare 1‐dimentional nanofiber for large‐scale manufacturing. Here in, we demonstrated chemical sensors based on the semiconducting nanofibers with core‐shell structure by simple single‐nozzle electrospinning with the spontaneous phase separation. The core‐shell structure nanofiber has large active sites which make it highly sensitive to chemical analytes. The thickness of the sensing shell can be tuned by controlling the mass ratio of core and shell components. As a demonstration, the nanofiber‐based sensor exhibits high sensitivity to low‐concentration ammonia (ppb level), as well as stability and reversibility. This unique fast single‐nozzle electrospinning technique used to fabricate semiconducting nanofibers with core‐shell structure provides a facile and designable process for the integration of multifunctional organic semiconducting layer into the organic electronic system.

A novel palladium-catalyzed protocol for the synthesis of 2-arylquinolines via tandem reaction of 2-aminostyryl nitriles with arylboronic acids has been developed with good functional group tolerance. The presented approach offers a new synthetic pathway toward the core structures of 2-arylquinolines compared to classical condensation reaction of (E)-2-aminostyryl aryl ketones. Moreover, the present synthetic route could be readily scaled up to gram quantity without difficulty. Preliminary mechanistic experiments showed that this transformation involves a nucleophilic addition of aryl palladium species to the nitrile to generate an aryl ketone intermediate followed by an intramolecular cyclization and dehydration to quinoline ring.

A palladium-catalyzed cascade reaction of 2′-acetyl-[1,1′-biphenyl]-2-carbonitriles with arylboronic acids is developed. This reaction affords a new class of seven-membered 5-arylidene-7-aryl-5H-di...

A practical, convenient, and highly selective method of synthesizing β-ketonitriles from the Pd-catalyzed addition of organoboron reagents to dinitriles has been developed. This method provides excellent functional-group tolerance, a broad scope of substrates, and the convenience of using commercially available substrates. The method is expected to show further utility in future synthetic procedures.

Graphical abstract Mg2TiO4−xNy demonstrates superior photocatalytic antibacterial activity under visible light illumination (λ ≥ 400 nm). Superoxide radicals (•O2−) can be generated by illuminating Mg2TiO4−xNy which are the reactive oxygen species (ROSs) for bacteria disinfection., Nitrogen doped Mg2TiO4 spinel, i.e. Mg2TiO4−xNy, has been synthesized and investigated as a photocatalyst for antibacterial activity. Mg2TiO4−xNy demonstrates superior photocatalytic activity for E. coli disinfection under visible light illumination (λ ≥ 400 nm). Complete disinfection of E. coli at a bacterial cell density of 1.0 × 107 CFU mL−1 can be achieved within merely 60 min. Mg2TiO4−xNy is capable of generating superoxide radicals (•O2−) under visible light illumination which are the reactive oxygen species (ROSs) for bacteria disinfection. DFT calculations have verified the importance of nitrogen dopants in improving the visible light sensitivity of Mg2TiO4−xNy. The facile synthesis, low cost, good biocompatibility and high disinfection activity of Mg2TiO4−xNy warrant promising applications in the field of water purification and antibacterial products.

A novel metal-free one-pot protocol for the synthesis of potential biologically active molecules 3-selenylindoles via intramolecular cyclization/selenylation with simple 2-vinylaniline has been developed with moderate to good yield, thus representing it as a facile route to diverse substitution patterns around the indole core. The reaction proceeded smoothly with a broad substrate scope and excellent functional group tolerance. Moreover, the present synthetic route could be readily scaled up to gram quantity without difficulty. Mechanistic studies have revealed that in situ formed selenium electrophile species may be the key intermediate for the selenocyclization process.

With the growing requirements for the renewability and sustainability of electronic products, environmentally friendly cellulose-based materials have attracted immense research interests and gained increasing prominence for electronic devices. Humidity sensors play an essential role in industries, agriculture, climatology, medical services, and daily life. Here, for the first time, we fabricate capacitive humidity sensors based on ionic conductive wood-derived cellulose nanopapers (WCNs). The WCN-based humidity sensors exhibited ultrahigh sensitivity, fast response, small hysteresis, and more importantly, a wide working range of relative humidity (RH). The sensors showed >104 times increase in the sensing signal over the 7-94% RH range at 20 Hz, while many reported humidity sensors with high sensitivity often have the working range limited to high RH levels. Our sensors can realize the distinction of nuances in humidity and exhibit outstanding noncontact skin humidity sensing properties. Flexible WCN-based humidity sensors were also fabricated, and they displayed excellent sensing properties with long-time stability, endowing them with multifunctional applications. The contrast humidity sensing experiment compared to the existing commercial humidity sensor further demonstrated the higher and faster response of our WCN-based sensors. Thus, this work provides effective guidance for the design of high-performance humidity sensors using nanopapers and opens a new dimension for a variety of future applications.

Homoleptic lanthanide complex Y[N(TMS)2]3 is an efficient homogeneous catalyst for the hydroboration reduction of secondary amides and tertiary amides to corresponding amines. A series of amides containing different functional groups such as cyano, nitro, and vinyl groups were found to be well-tolerated. This transformation has also been nicely applied to the synthesis of indoles and piribedil. Detailed isotopic labeling experiments, control experiments, and kinetic studies provided cumulative evidence to elucidate the reaction mechanism.

A lanthanide-catalyzed intermolecular hydroamination of 2-alkynylbenzonitriles with secondary amines has been disclosed, providing a streamlined access to a range of aminoisoindoles in moderate to excellent yields. The salient features of this reaction include high bond-formation efficiency, mild reaction conditions, 100 % atomic efficiency and good functional group tolerance. This methodology has also been successfully applied to the construction of other nitrogen-containing compounds, such as 5 H-imidazo[2,1-a]isoindoles and isoquinolines. A plausible mechanism for the formation of aminoisoindoles involving initial N-H activation by a lanthanide complex followed by C≡N insertion into a Ln-N bond to form an amidinate lanthanide intermediate, which undergoes the cyclization is proposed.

Neural progenitor cells (NPCs) play a key role not only in the maintenance of the adult central nervous system (CNS) but also in the ability to recover from injury and disease. In this study, we established a 96-well-based screening system to screen small molecules modulating the proliferation of NPCs. A compound library composed of 1280 compounds was screened. We found that the A1 adenosine receptor agonist cyclopentyladenosine (CPA) and the A2a adenosine receptor agonist CGS-21680 increased proliferation of NPCs. The A1 adenosine receptor agonist-induced cell proliferation was attenuated by A1 adenosine receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPA). Accordingly, the A2a adenosine receptor agonist-induced cell proliferation was attenuated by A2a adenosine receptor antagonist SCH-58261. Further study indicated that CPA and CGS-21680 treatment induced phosphorylation of extracellular signal-regulated kinase (ERK) and Akt, and CPA-induced or CGS-21680-induced cell proliferation was inhibited by ERK and Akt inhibitors. These results suggested that the activation of A1 and A2a adenosine receptor stimulated the proliferation of NPCs via the ERK and Akt signaling pathways.

The synthesis of 2,4-disubstituted quinazolines by a palladium-catalyzed reaction of arylboronic acids with N-(2-cyanoaryl)benzamides has been developed with moderate to excellent yields. The method shows good functional group tolerance. In particular, halogen and hydroxyl substituents, which are amenable for further synthetic elaborations, are well tolerated. Moreover, the present synthetic route could be readily scaled up to gram quantity without difficulty. The mechanism possibly involves nucleophilic addition to the nitrile function, forming an imine intermediate followed by an intramolecular addition to the amide and dehydration to the quinazoline ring.

The first example of the direct halosulfenylation of benzo[b]furans with commercially available disulfides and N-halosuccinimides has been achieved, providing an efficient metal-free synthetic pathway to access diverse 3-halo-2-thiobenzo[b]furans in moderate to excellent yields. In particular, a halogen (e.g., bromo or iodo) substituent on the benzo[b]furan ring is amenable for further synthetic elaborations thereby broadening the diversity of the products.

The Pd(II)-catalyzed cascade reactions of 2-(cyanomethoxy)chalcones with arylboronic acids were demonstrated, allowing the rapid construction of benzofuro[2,3-c]pyridine skeletons with excellent se...

The first example of the palladium-catalyzed tandem addition/cyclization of 2-(2-acylphenoxy)acetonitriles with arylboronic acids has been developed, providing a new strategy for the synthesis of 2-aroyl benzofurans with excellent chemoselectivity and wide functional group compatibility. Preliminary mechanistic experiments indicate that this tandem process involves sequential nucleophilic addition generating 2-(2-acylphenoxy)-1-phenylethan-1-one followed by an intramolecular cyclization. This methodology has also been applied to the synthesis of 2-aroyl indoles and the potent CYP19 inhibitor 1-(benzofuran-2-yl(phenyl)methyl)-1H-1,2,4-triazole.

The first example of the nickel-catalyzed tandem addition/cyclization of 2-(cyanomethyl)benzonitriles with arylboronic acids in 2-MeTHF has been developed, which provides the facile synthesis of aminoisoquinolines with good functional group tolerance under mild conditions. This chemistry has also been successfully applied to the synthesis of isoquinolones by the tandem reaction of methyl 2-(cyanomethyl)benzoates with arylboronic acids. The use of the bio-based and green solvent 2-MeTHF as the reaction medium makes the synthesis process environmentally benign. The synthetic utility of this chemistry is also indicated by the synthesis of biologically active molecules.

A palladium-catalyzed cascade reaction of 2'-acetyl-[1,1'-biphenyl]-2-carbonitriles with arylboronic acids is developed. This reaction affords a new class of seven-membered 5-arylidene-7-aryl-5

The first example of the palladium-catalyzed tandem addition/cyclization of 2-(benzylidenamino)benzonitriles with arylboronic acids has been developed. This transformation features good functional group tolerance and provides an alternative synthetic pathway to access 2,4-diarylquinazolines in moderate to good yields. A plausible mechanism for the formation of 2,4-diarylquinazolines involving sequential nucleophilic addition followed by an intramolecular cyclization is proposed.

Nitrogen doped Mg2TiO4 spinel, i.e. Mg2TiO4−xNy, has been synthesized and investigated as a photocatalyst for antibacterial activity. Mg2TiO4−xNy demonstrates superior photocatalytic activity for E. coli disinfection under visible light illumination (λ ≥ 400 nm). Complete disinfection of E. coli at a bacterial cell density of 1.0 × 107 CFU mL−1 can be achieved within merely 60 min. Mg2TiO4−xNy is capable of generating superoxide radicals ( O2−) under visible light illumination which are the reactive oxygen species (ROSs) for bacteria disinfection. DFT calculations have verified the importance of nitrogen dopants in improving the visible light sensitivity of Mg2TiO4−xNy. The facile synthesis, low cost, good biocompatibility and high disinfection activity of Mg2TiO4−xNy warrant promising applications in the field of water purification and antibacterial products.

Photocatalytic platforms are often used to remove pollutants from water. However, after long-term use, the surface of the platform is susceptible to the formation of bacterial biofilms, which reduces the efficiency of use and may cause secondary pollution of the water body. In this study, composite films were prepared by a casting method using a borneol-based polymer with anti-bacterial adhesion properties as a support and nano-TiO2 as a photocatalyst and bactericide. The extent of removal of methylene blue by the composite film could reach 91.5%. A remarkable anti-Staphylococcus aureus activity of the composite film under UV irradiation was observed. Additionally, the composite film was highly resistant to bacterial adhesion. These surfaces are based on the combination of two strategies into one system, which can kill bacteria as well as resisting bacterial adhesion. The multifunctional properties make the composite film suitable for applications in wastewater treatment.

Lanthanide-catalyzed alkynyl exchange through C-C single-bond cleavage assisted by a secondary amino group is reported. A lanthanide amido complex is proposed as a key intermediate, which undergoes unprecedented reversible β-alkynyl elimination followed by alkynyl exchange and imine reinsertion. The in situ homo- and cross-dimerization of the liberated alkyne can serve as an additional driving force to shift the metathesis equilibrium to completion. This reaction is formally complementary to conventional alkyne metathesis and allows the selective transformation of internal propargylamines into those bearing different substituents on the alkyne terminus in moderate to excellent yields under operationally simple reaction conditions.