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Abstract: In this work, CeO2−xNx materials have been prepared by the solution combustion method. All the prepared materials were characterized by powder-XRD, TEM, ICP-AES, RAMAN and XPS techniques. XRD and TEM confirmed 6-18 nm particles of CeO2−xNx materials (UC10, UC7, UC4 and UC1). Among different materials, UC10 showed the highest number of oxygen vacancies (Raman). With increase in U/C (fuel/oxidizer) ratio, the particle size decreased, whereas the specific surface area and oxygen vacancies increased. The oxygen vacancies are created because of charge imbalance and lattice distortion in ceria. The presence of N in ceria causes smaller crystallites and large specific surface area. XPS indicates N-Ce-O environment in CeO2−xNx materials. It is observed that oxygen vacancies created by nitrogen doping play an important role in cerium oxynitrides for CO oxidation reaction. The catalytic order of CeO2−xNx materials is as follows: UC10 > UC7 > UC4 > UC1. This is due to the larger number of oxygen vacancies possessed by UC10 material as compared to others. UC10 also showed an excellent 24 h time-on-stream stability for CO oxidation. The apparent activation energy of UC10 is found to be 51.1 kJ mol−1. This shows that CeO2−xNx materials are highly active and stable for CO oxidation.Graphical Abstract: [ABSTRACT FROM AUTHOR]

A general and facile method to prepare unquaternized C-bound boron enolates by a ligandcontrolled O-to-C isomerization is reported. Using this protocol, C-bound pinacolboron enolates have been isolated in pure form for the first time, and have been fully characterized by NMR spectroscopy and X-ray crystallography. In contrast to the general perception, such C-boron enolates are stable without coordinative saturation at the boron. Moreover, C-boron enolates present reactivities that are distinct from the O-boron enolates, and their applications in C-O and C-C bond formations are demonstrated. [ABSTRACT FROM AUTHOR]

BODIPY (boron dipyrromethene) derivatives and iron complexes are two types of functional compounds that have found wide applications in the fields of biology and medicine. The new class of cyclometalated Fe(II) complex with NCN pincer and meso‐phenyl‐4'‐ethynyl‐2,2':6',2”‐terpyridine BODIPY ligands of formula [Fe(L)(tpy‐BODIPY)], 1, in which HL:5‐methoxy‐1,3‐bis (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)benzene, tpy‐BODIPY: 8‐(4‐phenyl‐4'‐ethynyl‐2,2':6',2”‐terpyridine) BODIPY, has been synthesized and studied as mitochondria‐targeted photodynamic therapy (PDT). Complex 1 showed photocytotoxicity in HeLa cells at 500 nm with low dark toxicity. The phototoxicity of complex 1 on the nontumorigenic MRC‐5 cell line showed the same trend observed for HeLa cells, that is moderately photocytotoxic against the nontumorigenic MRC‐5 cell line (IC50 = 36.21 μM). Moreover, complex 1 selectively localizes into mitochondria of the HeLa cells. The photophysical properties, cellular uptake, reactive oxygen species (ROS) generation, and cellular apoptosis of complex 1 have also been studied.Overall, the new Fe(II) complex with BODIPY moiety is significantly photocytotoxic in HeLa cells when irradiated with visible light of 500 nm giving as mitochondria targeting. Therefore, we present cyclometalated Fe(II) pincer complex induced mitochondria‐targeted PDT involving the BODIPY moiety that develops persuasively designed photoactivatable Fe(II) complexes. [ABSTRACT FROM AUTHOR]

We reported a synthesis of quaternary B-C-N-O alloys containing boron, carbon, nitrogen, and oxygen atoms by using melamine-boric acid adduct colloidal solutions (C 3 N 6 H 6 ·2H 3 BO 3 ) as a precursor via chemical reactions. The nanocrystalline BCNO was observed by scanning electron microscope. Results from X-ray diffraction show a prominent peak at 28.13° for BCNO, indicating the interlayer distance of 0.317 nm. Elemental compositions and chemical bonds of BCNO were verified by X-ray photoemission spectroscopy. Electrical measurement of BCNO-based field effect transistors gave 0.3 cm 2 V −1 s −1 of charge mobility, 0.77 eV of band gap with 10 5 of on/off ratio. [ABSTRACT FROM AUTHOR]

Conspectus: Due to the complexity of biological systems and samples, specific capture and targeting of certain biomolecules is critical in much biological research and many applications. cis-Diol-containing biomolecules, a large family of important compounds including glycoproteins, saccharides, nucleosides, nucleotides, and so on, play essential roles in biological systems. As boronic acids can reversibly bind with cis-diols, boronate affinity materials (BAMs) have gained increasing attention in recent years. However, real-world applications of BAMs are often severely hampered by three bottleneck issues, including nonbiocompatible binding pH, weak affinity, and difficulty in selectivity manipulation. Therefore, solutions to these issues and knowledge about the factors that influence the binding properties are of significant importance. These issues have been well solved by our group in past years. Our solutions started from the synthesis and screening of boronic acid ligands with chemical moieties favorable for binding at neutral and acidic pH. To avoid tedious synthesis routes, we proposed a straightforward strategy called teamed boronate affinity, which permitted facile preparation of BAMs with strong binding at neutral pH. To enhance the affinity, we confirmed that multivalent binding could significantly enhance the affinity toward glycoproteins. More interestingly, we observed that molecular interactions could be significantly enhanced by confinement within nanoscale spaces. To improve the selectivity, we investigated interactions that govern the selectivity and their interplays. We then proposed a set of strategies for selectivity manipulation, which proved to be useful guidelines for not only the design of new BAMs but also the selection of binding conditions. Applications in metabolomic analysis, glycoproteomic analysis, and aptamer selection well demonstrated the great potential of the prepared BAMs. Molecular imprinting is an important methodology for creating affinity materials with antibody-like binding properties. Boronate affinity-based covalent imprinting is a pioneering approach in molecular imprinting, but only a few cases of successful imprinting of glycoproteins by this method were reported. With sound understanding of boronate affinity, we developed two facile and generally applicable boronate affinity-based molecular imprinting approaches. The resulting boronate affinity molecularly imprinted polymers (MIPs) exhibited dramatically improved binding properties, including biocompatible binding pH range, enhanced affinity, improved specificity, and superb tolerance to interference. In terms of nanoconfinement effect, we explained why the binding pH range was widened and why the affinity was enhanced. The excellent binding properties made boronate affinity MIPs appealing alternatives to antibodies in promising applications such as disease diagnosis, cancer-cell targeting, and single-cell analysis. In this Account, we survey the key aspects of BAMs, the efforts we made to solve these issues, and the connections between imprinted and nonimprinted BAMs. Through this survey, we wish to pave a sound fundamental basis of the dependence of binding properties of BAMs on the nature and structure of the ligands and the supporting materials, which can facilitate the development and applications of BAMs. We also briefly sketch remaining challenges and directions for future development. [ABSTRACT FROM AUTHOR]

A new multifunctional probe made up of boron dipyrromethene (BODIPY) and benzimidazole neighboring phenol was designed and synthesized. This probe displays a colorimetric recognition of Hg 2+ and a ‘turn off’ fluorescent response to Cr 3+ at physiological condition. The ‘in situ’ ensemble of host and Hg 2+ shows a selective and ratiometric detection of I − via the formation of three-component ensemble. These systems were further used to detect their corresponding targets in real water sample with acceptable recovery. Compared to the comprehensive report of the single-target responsive chemosensor, these results provided an approach to design the challenging multifunctional probe. [ABSTRACT FROM AUTHOR]

The synthesis of the Cu-borate complexes [(6Mes)Cu(HBR3)] featuring the unusual [HBEt3]− ( 5) and [HB(C6F5)3]− ( 6) ligands is described. Experimental and computational studies show both compounds feature a direct Cu-H interaction, but that while 5 is two-coordinate, 6 displays an additional, stabilizing Cu-Cipso(C6F5) interaction. [ABSTRACT FROM AUTHOR]

The synthesis of the Cu-borate complexes [(6Mes)Cu(HBR3)] featuring the unusual [HBEt3]− ( 5) and [HB(C6F5)3]− ( 6) ligands is described. Experimental and computational studies show both compounds feature a direct Cu-H interaction, but that while 5 is two-coordinate, 6 displays an additional, stabilizing Cu-Cipso(C6F5) interaction. [ABSTRACT FROM AUTHOR]

The design, synthesis, and characterization of a series of thiazole-appended boron-dipyrromethene (BODIPY) derivatives 1- 4 is reported. The fluorescence emission colors of 1- 4 were fine-tuned by modulating the dihedral angle between BODIPY and thiazole by judiciously varying the number of methyl substituents on both the BODIPY and thiazole moieties. Compounds 1 and 2 with fewer methyl substituents on the BODIPY core showed a large Stokes shift (≈110 nm) relative to derivatives 3 and 4 with more methyl substituents. In addition, the optical properties of 1 and 2 are sensitive to the pH of the medium. The experimentally observed results were corroborated with theoretical calculations. [ABSTRACT FROM AUTHOR]

New borophosphates Li3Cs2M2B3P6O24 (M = Pb, Sr) have been synthesized by high-temperature solid-state reactions. The single-crystal X-ray diffraction data reveal their non-centrosymmetric cubic space group P213 and lattice parameters of a = 12.7246(3) Å and 12.687(2) Å and V = 2060.31(8) Å3 and 2042.3(4) Å3 for Li3Cs2Pb2B3P6O24 and Li3Cs2Sr2B3P6O24, respectively. They are three-dimensional (3D) [BP2O8]3−∞ anionic frameworks formed by a new double six-membered ring building unit consisting of BO4 and PO4 units joined alternately. Interestingly, such a double six-membered ring is regarded as the structural variation of the 12-membered ring in the known KSrBP2O8, fusing at the BO4 tetrahedron induced by the coexistence of the Li+ and Cs+ cations with their large size difference. The title compounds show weak SHG intensity and exhibit photoluminescence emissions at 410 nm for Li3Cs2Pb2B3P6O24 and 440 nm for Li3Cs2Sr2B3P6O24. [ABSTRACT FROM AUTHOR]

New borophosphates Li3Cs2M2B3P6O24 (M = Pb, Sr) have been synthesized by high-temperature solid-state reactions. The single-crystal X-ray diffraction data reveal their non-centrosymmetric cubic space group P213 and lattice parameters of a = 12.7246(3) Å and 12.687(2) Å and V = 2060.31(8) Å3 and 2042.3(4) Å3 for Li3Cs2Pb2B3P6O24 and Li3Cs2Sr2B3P6O24, respectively. They are three-dimensional (3D) [BP2O8]3−∞ anionic frameworks formed by a new double six-membered ring building unit consisting of BO4 and PO4 units joined alternately. Interestingly, such a double six-membered ring is regarded as the structural variation of the 12-membered ring in the known KSrBP2O8, fusing at the BO4 tetrahedron induced by the coexistence of the Li+ and Cs+ cations with their large size difference. The title compounds show weak SHG intensity and exhibit photoluminescence emissions at 410 nm for Li3Cs2Pb2B3P6O24 and 440 nm for Li3Cs2Sr2B3P6O24. [ABSTRACT FROM AUTHOR]

Reported is a versatile new oxidative method for the arylation of activated methylene species. Under mild reaction conditions (RT to 40 °C), Cu(OTf)2 mediates the selective coupling of functionalized aryl boron species with a variety of stabilized sp3-nucleophiles. Tertiary malonates and amido esters can be employed as substrates to generate quaternary centers. Complementing either traditional cross-coupling or SNAr protocols, the transformation is chemoselective in the presence of halogen electrophiles, including aryl bromides and iodides. Substrates bearing amide, sulfonyl, and phosphonyl groups, which are not amenable to coupling under mild Hurtley-type conditions, are suitable reaction partners. [ABSTRACT FROM AUTHOR]

Redistribution of boron during the silicon solidification refining process using an Si-Al melt has been studied by electron probe microanalysis and inductively coupled plasma mass spectrometry. The results and the effects of alloy composition, cooling rate and heating method on boron removal indicate that silicon can be purified by the segregation of boron to the α-Al component of the eutectic phase after the alloy solidification. Furthermore, use of lower cooling rate and Si-Al alloy with low Si content shows enhanced boron redistribution. The lowest refining ratio (0·17) and the highest removal fraction of boron (74·3%) were achieved in 22·8 at-%Si-Al alloy at a cooling rate of 3 K min−1. Induction heating was used to obtain agglomerated Si plates and also recycled ∼73·9% (by area) of byproduct (i.e. Si-Al alloy) from 35·4 at-%Si-Al alloy. [ABSTRACT FROM AUTHOR]

A new domino strategy for selective synthesis of enaminones and their difluoroboron complexes through aryl migration has been developed. The reaction features low-cost and readily accessible starting materials, reliable scalability, and bond-forming efficiency as well as simple one-pot operation, which makes this strategy highly viable for future applications. [ABSTRACT FROM AUTHOR]

A series of boron difluoride--3-acyl-4-hydroxycoumarin complexes were synthesized in good yields in three steps starting from 4-hydroxycoumarins. The boron complexes showed strong luminescence in the green--yellow region and are compatible with surface imaging applications. [ABSTRACT FROM AUTHOR]

A cubic cationic cage is rationally designed by using tridentate boron-imidazolate ligands to link tetrahedral metal Zn(ii) centers, which displays excellent properties in the Cr2O72− exchange and can reduce Au3+ ions into Au nanoparticles directly. [ABSTRACT FROM AUTHOR]

Arising from Y. Tian et al. 493, 385-388 (2013)Tian et al. report synthesis of 'nanotwinned' cubic boron nitride ('nt-cBN'). These authors claim that its unprecedented Vickers hardness of 108 GPa is due to nanotwinning, and that hardening of cBN is continuous with decreasing twin thickness down to the smallest size investigated, in contrast to the expected reverse Hall-Petch effect. We demonstrate here that it has been known for tens of years that 'nt-cBN' (refs 2-4) hardens owing to a complex of phenomena associated with its microstructure and defects; we also consider that Tian et al. provide no proof that the hardness of 'nt-cBN' is larger than 85 GPa, which is the previously reported maximum for nanostructured boron nitride. Thus the claim of continuous hardening down to a few nanometres twin thickness is, in our opinion, unjustified. There is a Reply to this Brief Communication Arising by Tian, Y. et al. Nature 502, http://dx.doi.org/10.1038/nature12621 (2013). [ABSTRACT FROM AUTHOR]

Review: 50 refs. [ABSTRACT FROM AUTHOR]