•The two-photon (TP) photosensitizers (PS) of maximum absorption at 808 nm and maximum fluorescence at 660 nm can be potential for deep-seated tumor imaging and therapy.•The boron dipyrromethene ...(BDP) structure used in TP photodynamic therapy (PDT) possess favorable photophysical property (i.e., high molar extinction coefficients, superior fluorescent quantum yields, outstanding photo stability), and the indo-BDP in meso-position can efficiently improve the singlet oxygen quantum yield (0.39).•The cationic group in TP PS can efficiently improve the PDT efficacy (IC50=25.5 nM) compared with two neutral contrastive molecules (PG-Car-BDP and C10-Car-BDP).•The cationic PS TP-Car-BDP can efficiently target to tumor in vivo due to the structure inherent targeting.
Two-photon (TP) have been innovatively researched in bio-imaging and photodynamic therapy (PDT) due to the near-infread (NIR) absorption and excellent spatial accuracy, especially for the subcutaneous and deep-seated tumor. For TP excited photosensitizers (PS), the NIR absorption and enough triplet state energy can be simultaneously realized by semi-excited mode. Thus, we reported a boron dipyrromethene based cationic two-photon photosensitizer (TP-Car-BDP) to promote the tumor targeting and optical physical properties for better imaging and therapeutic effect, using two neutral molecules (PG-Car-BDP, C10-Car-BDP) as comparison. As expected, the cationic group could accelerate oil-water balance and cellular uptake, realize structure-inherent targeting in vivo, and induced early apoptosis in PDT. The imaging and therapeutic property of TP-Car-BDP excited by one/two-photon was also compared to illustrate efficacy of TP. Moreover, the high singlet oxygen quantum yield (0.39) and excellent phototoxicity (IC50 of 25.5 nM, MB was 2960 nM) revealed the potential therapeutic capacity.
In this work, boron and nitrogen co-doped hierarchical porous carbon (BN-HPC) with a relatively high contents of boron (3.97 wt%) and nitrogen (12.10 wt%) is synthesized by a method combined with ...template process and carbonization of hierarchical porous resin using melamine and boric acid as nitrogen and boron sources, respectively. The co-doping method achieves a high boron doping level (8 times of that of single boron doped sample) which is of great significance in increasing the doping efficiency of boron. The hierarchical porosity, structure and surface chemical properties are studied in detail via various means, such as Transmission Electron Microscopy, N2 sorption, X-ray diffraction, X-ray photoelectron spectroscopy and elemental analysis, etc. Owing to the synergistic effect of hierarchical porosity and heteroatoms doping, BN-HPC exhibits greatly improved electrochemical capacitive performance of 304 F g−1 at a current density of 0.1 A g−1 and good rate capability (189 F g−1 remained at a current density of 10 A g−1). The strategy of synthesis is facile and very effective.
Display omitted
At the atomic-cluster scale, pure boron is markedly similar to carbon, forming simple planar molecules and cage-like fullerenes. Theoretical studies predict that two-dimensional (2D) boron sheets ...will adopt an atomic configuration similar to that of boron atomic clusters. We synthesized atomically thin, crystalline 2D boron sheets (i.e., borophene) on silver surfaces under ultrahigh-vacuum conditions. Atomic-scale characterization, supported by theoretical calculations, revealed structures reminiscent of fused boron clusters with multiple scales of anisotropic, out-of-plane buckling. Unlike bulk boron allotropes, borophene shows metallic characteristics that are consistent with predictions of a highly anisotropic, 2D metal.
Since their discovery in 2005, covalent organic frameworks (COFs) have attracted interest as potential materials for gas storage, catalysis, energy storage, and other applications because of their ...ability to periodically and reliably organize designed functionality into high surface area materials. Most of the first examples relied on boron-containing linkages, which suffer from hydrolytic and oxidative instability that limit their utility. In this Perspective, we describe the trend toward more robust linkages by highlighting the design, synthesis, and properties of several recent examples. The continued development of new COF chemistries, along with improved understanding of their formation and control of their final form, will provide a means to harness their molecularly precise solid-state structures for useful purposes.
A hybrid transition‐metal/radical process is described that results in the addition of organozinc reagents and alkyl halides across alkenyl boron reagents in an enantioselective catalytic fashion. ...The reaction can be accomplished both intermolecularly and intramolecularly, providing useful product yields and high enantioselectivities in both manifolds.
A radical hybrid: The dicarbofunctionalization of vinylB(pin) was achieved through the use of a nickel‐based chiral catalyst. The reaction employs alkyl halide and organozinc reagents and can be accomplished with good levels of enantioselectivity in an intra‐ or intermolecular fashion.
Yapı elemanları için en önemli durabilite özelliklerinden birisi de yüksek sıcaklık etkisine maruz kaldıktan sonra göstermiş oldukları dayanımdır. Bu çalışmada, öğütülmüş yüksek fırın cürufu (İÖYFC), ...bazalt (BZ) ve üleksit (U) katkılarıyla üretilen beton örneklerin yüksek sıcaklık etkisi altındaki özellikleri araştırılmıştır. Bu amaçla, TS 802 standardında belirtilen şartlara uygun beton karışımında ince agreganın yerine kütlece yüksek fırın cürufu %10-20, bazalt %10-20 ve üleksit %1-2 oranlarında eklenmiştir. Yüksek fırın cürufu, bazalt ve üleksit katkılı 7 ve 28 günlük örnekler bir saat 600 ve 800 °C sıcaklık etkisinde bırakılarak havada ve suda olmak üzere iki farklı soğutma rejimine tabi tutulmuştur. Yüksek sıcaklığa maruz bırakılan örneklere basınç dayanımı ve ultrasonik dalga hızı deneyleri yapılmıştır. Ayrıca örnekler üzerinde 7 ve 28 günlük basınç dayanımı, ultrases geçiş hızı ve aşınma deneyleri yapılmıştır. 600 °C yüksek sıcaklık etkisine maruz bırakılan numunelerin havada soğutma sonrası basınç dayanım değerleri referans numunesine göre %40-%20-%8 oranlarında ve suda soğutma sonrası basınç dayanım değerleri referans numunesine göre %60-%55-%42 oranlarında İÖYFC10, İÖYFC20 ve U1 katkısının yüksek sıcaklık etkisine karşı dayanım değerlerini arttırdığı göstermektedir. Bu değerlendirme ile yüksek fırın cürufu ve üleksit katkısının ince agrega olarak beton karışımında yüksek sıcaklık etkilerine karşı dayanıklı beton üretiminde kullanılabileceğini göstermiştir.Anahtar Kelimeler: Bazalt, Yüksek fırın cürufu, Durabilite, Yüksek sıcaklık
For many years, organoboron compounds have been expected to show excellent electron-injecting and -transporting properties. However, lowest unoccupied molecular orbital (LUMO) energy levels (E LUMO) ...of B-containing π-conjugated molecules are mostly higher than −4.0 eV and their electron mobilities are usually less than 10–2 cm2 V–1 s–1. In this work, we experimentally prove the remarkably high electron affinity and high electron mobility of organoboron compounds. Our strategy is to incorporate multiple boron–nitrogen coordination bonds (B←N) into azaacenes. We synthesized quadruply B←N-fused dibenzo-azaacene (QBNA) through one-pot multifold borylation cyclization reaction. The incorporation of four B←N units greatly changes the electronic structures and properties and significantly downshifts the electronic energy levels of QBNA. QBNA shows a E LUMO of as low as −4.58 eV, which is among the lowest for n-type organic semiconductors. Single-crystal organic field-effect transistors of QBNA display unipolar n-type characteristic with an electron mobility of up to 1.60 cm2 V–1 s–1 together with excellent ambient stability. This study thus provides a design strategy for high-performance n-type organic semiconductors and high electron-affinity π-systems based on organoboron chemistry.
Dodecaborate anions of the type B12X122- and B12X11Y2- (X=H, Cl, Br, I and Y=OH, SH, NH3+, NR3+) form strong (Ka up to 106Lmol-1, for B12Br122-) inclusion complexes with gamma-cyclodextrin ...(gamma-CD). The micromolar affinities reached are the highest known for this native CD. The complexation exhibits highly negative enthalpies (up to -25kcalmol-1) and entropies (TDeltaS up to -18.4kcalmol-1, both for B12I122-), which position these guests at the bottom end of the well-known enthalpy-entropy correlation for CDs. The high driving force can be traced back to a chaotropic effect, according to which chaotropic anions have an intrinsic affinity to hydrophobic cavities in aqueous solution. In line with this argument, salting-in effects revealed dodecaborates as superchaotropic dianions.
Unsymmetric 1,1-diboryl alkenes bearing one −BPin (BPin = pinacolatoboryl) and one −BDan (BDan = 1,8-diaminonaphthalatoboryl) substituent each were hydrogenated in high yield and enantioselectivity ...using C 1-symmetric pyridine(diimine) (PDI) cobalt complexes. High activities and stereoselectivities were observed with an array of 2-alkyl-, 2-aryl-, and 2-boryl-substituted 1,1-diboryl alkenes, giving rise to enantioenriched diborylalkane building blocks. Systematic study of substrate substituent effects identified competing steric and electronic demands in the key activating role of the boron substituents, whereby sterically unencumbered boronates such as −BDan, −BCat (BCat = catecholatoboryl), and −Beg (Beg = ethylene glycolatoboryl) promote the hydrogenation of trisubstituted alkenes by enabling irreversible α-boron-directed insertion pathways to achieve otherwise challenging hydrogenations of trisubstituted alkenes. Deuterium-labeling studies with 1,1-diboryl alkenes support an insertion pathway generating a chiral intermediate with two different boron substituents and cobalt bound to the same carbon.
Deep‐ultraviolet nonlinear optical (DUV NLO) crystals are the key materials to extend the output range of solid‐state lasers to below 200 nm. The only practical material KBe2BO3F2 suffers high ...toxicity through beryllium and strong layered growth. Herein, we propose a beryllium‐free material design and synthesis strategy for DUV NLO materials. Introducing the (BO3F)4−, (BO2F2)3−, and (BOF3)2− groups in borates could break through the fixed 3D B–O network that would produce a larger birefringence without layering and simultaneously keep a short cutoff edge down to DUV. The theoretical and experimental studies on a series of fluorooxoborates confirm this strategy. Li2B6O9F2 is identified as a DUV NLO material with a large second harmonic generation efficiency (0.9×KDP) and a large predicted birefringence (0.07) without layering. This study provides a feasible way to break down the DUV wall for NLO materials.
Be gone: A strategy to prepare a beryllium‐free material that does not grow in layers for deep‐UV (DUV) nonlinear optical (NLO) materials is developed and carried out. Introducing the (BO3F)4−, (BO2F2)3−, and (BOF3)2− groups in borates is a feasible way to balance the criteria of deep‐UV NLO materials, breaking down the DUV wall for NLO materials.
PDF
