Various 2-aryl-3-arylazoacrylonitriles are synthesized while attempting the intramolecular N-arylation of 5-aminopyrazoles, using the hypervalent iodine reagent. The synthesis involves phenyl iodine diacetate-assisted ring opening of 5-aminopyrazoles at room temperature. A plausible mechanism for the formation of azoalkenes is proposed.
Experimental and computational studies on the directing ability of chalcogenoether motifs in Pd-catalyzed atroposelective C−H olefination and allylation are presented. The thioether motif was found to a superior directing group compared to the corresponding ether (−OR) and selenoether in terms of reactivity and enantiocontrol. The selenoether unit (−SeMe) was used for the first time as a suitable directing group in asymmetric C−H activation.
We present herein our experimental and DFT computational studies on the directing ability of chalcogenoether motifs in Pd-catalyzed atroposelective C−H functionalization. The thioether motif was found to be a superior directing group compared to the corresponding ether and selenoether in terms of reactivity and enantiocontrol. Remarkably, DFT calculation provided a predictive model for the optimization of reaction conditions and the interpretation of the origin of enantioselectivity. Both Pd-catalyzed enantioselective C−H olefination and allylation reactions were successfully developed using chiral phosphoric acids as efficient ligands, providing a broad range of axially chiral biaryls in good yields with excellent enantioselectivities. The highly enantio- and diastereoselective construction of polyaryls bearing multiple stereogenic axes, gram-scale reaction and various chemical transformations make this protocol more attractive and significant.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Gang Liao, Tao Zhang, Liang Jin, Bing‐Jie Wang, Cheng‐Kai Xu, Yu Lan, Yu Zhao, Bing‐Feng Shi
onlinelibrary.wiley.com/doi/10.1002/anie.202115221
In this work, efficient synthesis of isoindolin-1-one-3-phosphonates under catalyst- and solvent-free conditions was reported to afford the desired compounds in excellent yields with potent pharmacological properties. The synthesis method involves the preparation of isoindolin-1-one-3-phosphonates by a “one-pot” three-component reaction of 2-formylbenzoic acid with primary amines and dimethyl phosphite under solvent- and catalyst-free conditions. All new compounds were characterized by 1H NMR, 13C NMR, FT-IR and elemental analysis techniques. The compounds were investigated for their bioactivities against a group of microorganisms, Leishmania major, Toxoplasma gondii parasites, and the DA-MB-231 and MCF-7 cancer cell lines in vitro. Compound 4a was found to be the most active against L. M. luteus, L. monocytogenes and C. albicans microorganisms, with inhibition zones of 35, 22 and 38 mm, respectively. The compounds were also investigated for their antiparasitic activities, and compounds 4a and 4b were the most active against L. major amastigotes and promastigotes with EC50 < 1 μM. All tested compounds had potent anticancer activity against the MDA-MB-231 and MCF-7 human cell lines with EC50 < 1.5 μM. Compounds 4a and 4b are good drug candidates for antimicrobial, antileishmanial and anticancer drug discovery, and further in vivo studies are highly recommended prior to any clinical trials.
A porous liquid-crystalline network can swell in water for actuation through both water absorption and order–disorder phase transition, and be loaded with functional fillers to display reconfigurable functions.
A porous liquid-crystalline network (LCN), prepared by using a template method, was found to exhibit peculiar actuation functions. The creation of porosity makes the initially hydrophobic LCN behave like a hydrogel, capable of absorbing a large volume of water (up to ten times the sample size of LCN). When the amount of absorbed water is relatively small (about 100 % swelling ratio), the porous LCN displays anisotropic swelling in water and, in the same time, the retained uniaxial alignment of mesogens ensures a thermally induced shape change associated with a LC-isotropic phase transition. Combining the characteristic actuation mechanisms of LCN (order–disorder transition of mesogens) and hydrogel (water absorption), such porous LCNs can be explored for versatile stimuli-triggered shape transformations. Moreover, the porosity enables loading/removal/reloading of functional fillers such as ionic liquids, photothermal dyes and fluorophores, which imparts the porous LCN actuator with reconfigurable functions such as ionic conductivity, light-driven locomotion, and emissive color.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Jie Jiang, Li Han, Feijie Ge, Yaoyu Xiao, Ruidong Cheng, Xia Tong, Yue Zhao
onlinelibrary.wiley.com/doi/10.1002/anie.202116689
The temporal and spatial control of natural systems has aroused great interest for the creation of synthetic mimics. Herein, a dynamic boronic ester based non-equilibrium self-assembly strategy has enabled the creation of programmable and transient supramolecular chiral G-quadruplex hydrogels with tunable lifetimes from minutes, to hours, to days, as well as high transparency and conductivity, excellent injectability, and self-healing properties.
The temporal and spatial control of natural systems has aroused great interest for the creation of synthetic mimics. By using boronic ester based dynamic covalent chemistry and coupling it with an internal pH feedback system, we have developed a new chemically fueled reaction network for non-equilibrium supramolecular chiral G-quadruplex hydrogels with programmable lifetimes from minutes, to hours, to days, as well as high transparency and conductivity, excellent injectability, and rapid self-healing properties. The system can be controlled by the kinetically controlled in situ formation and dissociation of dynamic boronic ester bonds between the cis-diol of guanosine (G) and 5-fluorobenzoxaborole (B) in the presence of chemical fuels (KOH and 1,3-propanesultone), thereby leading to a precipitate-solution-gel-precipitate cycle under non-equilibrium conditions. A combined experimental-computational approach showed the underlying mechanism of the non-equilibrium self-assembly involves aggregation and disaggregation of right-handed helical G-quadruplex superstructures. The proposed dynamic boronic ester-based non-equilibrium self-assembly strategy offers a new option to design next-generation adaptive and interactive smart materials.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Xiao‐Qiao Xie, Yunfei Zhang, Yujia Liang, Mengke Wang, Yihan Cui, Jingjing Li, Chun‐Sen Liu
onlinelibrary.wiley.com/doi/10.1002/anie.202114471
“Dynamic” helical metal-based polymers can offer adaptability and functionality, but such systems remain unexplored. The titled polymers display mirror-image CD spectra for β-(L and D)-arabinopyranosyl sidechains (signifying helical coiling with preferred, opposite screw sense); the responsiveness and dynamic nature of the folded conformations are evident, and developments toward helicity-governed activity are described.
The study of metallopolymers with controllable helical sense remains in its infancy. We report arabinose-functionalized (Zn-salphen)-based conjugated polymers that display mirror-image circular dichroism spectra for L- and D-sugar sidechains respectively, signifying ordered (helical) coiling of the polymer backbone with opposite screw-sense preferences. The observation of different spectroscopic behavior and Cotton effects for a variety of solvents (in a reversible manner) and temperatures, ascribed to changes in the extent of intrachain (Zn⋅⋅⋅O(salphen) and π-stacking) interactions between Zn-salphen moieties, thus indicate the flexible, responsive and dynamic nature of the folded helical conformation in these systems. An application study signifying that activity can be governed by the structure and helical sense of the polymer is described.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Chao Zhao, Shuangshuang Meng, Hei‐Nga Chan, Xueli Wang, Hung‐Wing Li, Michael C. W. Chan
onlinelibrary.wiley.com/doi/10.1002/anie.202115712
Pressure-driven two-step second-harmonic-generation (SHG) switching has been achieved in polar BiOIO3, by using an in situ high-pressure polarization-dependent single-crystal SHG measurement system. The step-wise suppression of the lone-pair electrons on I5+ cations has been demonstrated to be responsible for the switching phenomenon in BiOIO3, and materials with multi-stabilities are crucial to next-generation switch and information storage devices.
Materials with multi-stabilities controllable by external stimuli have potential for high-capacity information storage and switch devices. Herein, we report the observation of pressure-driven two-step second-harmonic-generation (SHG) switching in polar BiOIO3 for the first time. Structure analyses reveal two pressure-induced phase transitions in BiOIO3 from the ambient noncentrosymmetric phase (SHG-high) to an intermediate noncentrosymmetric phase (SHG-intermediate) and then to a centrosymmetric phase (SHG-off). The three-state SHG switching was inspected by in situ high-pressure powder SHG and polarization-dependent single-crystal SHG measurements. Local structure analyses based on the in situ Raman spectra and X-ray absorption spectra reveal that the SHG switching is caused by the step-wise suppression of lone-pair electrons on the [IO3]− units. The dramatic evolution of the functional units under compression also leads to subtle changes of the optical absorption edge of BiOIO3. Materials with switchable multi-stabilities provide a state-of-art platform for next-generation switch and information storage devices.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Dequan Jiang, Huimin Song, Ting Wen, Zimin Jiang, Chen Li, Ke Liu, Wenge Yang, Hongwei Huang, Yonggang Wang
onlinelibrary.wiley.com/doi/10.1002/anie.202116656
A distinct molecule-selective cobalt disulfide fence is proposed to be capable of solving the activity–stability trade-off of highly active cobalt-doped molybdenum disulfide catalysts. This fence completely encloses the catalyst and prevents species that would poison the catalyst from reaching it, but allows catalytic reaction-related species to diffuse freely. In situ spectroscopy uncovers its underlying mechanism.
Non-precious-metal (NPM) catalysts often face the formidable challenge of a trade-off between long-term stability and high activity, which has not yet been widely addressed. Herein we propose a distinct molecule-selective fence as a promising concept to solve this activity-stability trade-off. The fence encloses the catalyst and prevents species poisonous to the catalyst from reaching it, but allows catalytic reaction-related species to diffuse freely. We constructed a CoS2 fence layer on the external surface of highly active cobalt-doped MoS2, achieving a remarkable catalytic stability towards the alkaline hydrogen evolution reaction and improved activity. In situ spectroscopy uncovered the underlying molecular mechanism of the CoS2 fence for breaking the activity-stability trade-off of the MoS2 catalyst. This work offers valuable guidance for rationally designing efficient and stable NPM catalysts.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Jingbin Huang, Mengyao Hao, Baoguang Mao, Lirong Zheng, Jie Zhu, Minhua Cao
onlinelibrary.wiley.com/doi/10.1002/anie.202114899
A dual catalysis strategy via carboxylate species featuring weak nucleophilicity and basicity is used for the direct carbonylative polymerization of various epoxides for the production of original advanced polyhydroxyalkanoates (PHAs) with high molecular weight and tunable functionalization. This study represents a rare example of PHAs synthesis using epoxides and carbon monoxide as raw materials.
Polyhydroxyalkanoates (PHAs) are a unique class of commercially manufactured biodegradable polyesters with properties suitable for partially substituting petroleum-based plastics. However, high costs and low volumes of production have restricted their application as commodity materials. In this study, tri-metallic complexes were developed for carbonylative polymerization via a dual catalysis strategy, and 17 products of novel PHAs with up to 38.2 kg mol−1Mn values were discovered. The polymerization proceeds in a sequential fashion, which entails the carbonylative ring expansion of epoxide to β-lactone and its subsequent ring-opening polymerization that occurs selectively at the O-alkyl bond via carboxylate species. The wide availability and structural diversity of epoxide monomers provide PHAs with various structures, excellent functionalities, and tunable properties. This study represents a rare example of the preparation of PHAs using epoxides and carbon monoxide as raw materials.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Jin‐Chuang Yang, Jun Yang, Wen‐Bing Li, Xiao‐Bing Lu, Ye Liu
onlinelibrary.wiley.com/doi/10.1002/anie.202116208
To avoid the poor conductivity of most pristine metal–organic frameworks, a free-standing metal–organic layer (MOL) was exploited to construct diverse composites by a facile post-synthetic strategy. The structural superiority of the MOLs composites contributes to the excellent and durable performance of electrocatalytic CO2 reduction into formate.
2D metal–organic-framework (MOF) based composites have emerged as promising candidates for electrocatalysis due to their high structural flexibility and fully exposed active sites. Herein, a freestanding metal–organic layer (MOL) with a 2D kgd (kagome dual) lattice was constructed with abundant surface oxygenate groups serving as anchoring sites to immobilize diverse guests. Taking Bi as an example, tetragonal Bi2O3 nanowires can be uniformly grown on MOLs after solvothermal treatment, the structural evolution of which was followed by ex situ electron microscopy. The as-prepared Bi2O3/MOL exhibits excellent CO2 electroreduction activity towards formate reaching a specific current of 2.3 A mgBi−1 and Faradaic efficiencies of over 85 % with a wide potential range from −0.87 to −1.17 V, far surpassing Bi2O3/UiO (a 3D Zr6-oxo based MOF) and Bi2O3/AB (Acetylene Black). Such a post-synthetic modification strategy can be flexibly extended to develop versatile MOL composites, highlighting the superiority of optimizing MOL-based composites for electrocatalysis.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Hang Liu, Hongguang Wang, Qian Song, Kathrin Küster, Ulrich Starke, Peter A. Aken, Elias Klemm
onlinelibrary.wiley.com/doi/10.1002/anie.202117058
An active role of achiral nanoparticles in regulating supramolecular chirality of the nanocomposites is reported. Nanoparticle-curvature-dependent supramolecular chirality in nanotubular composites was discovered, where small-sized nanoparticles of high curvature and large-sized nanoparticles of low curvature lead to nanotubular composites with opposite chirality.
Nanoscale curvature-dependent interactions are of paramount importance in biological systems. Here, we report that nanoscale curvature plays an important role in regulating the chirality of self-assembled nanocomposites from chiral organic molecules and achiral nanoparticles. Specifically, we show that the supramolecular chirality of the nanocomposites markedly depends on the nanoparticle curvature, where small-sized nanoparticles of high curvature and large-sized nanoparticles of low curvature lead to nanocomposites with opposite chirality. Quantitative kinetic experiments and molecular dynamics simulations reveal that nanoparticle curvature plays a key role in promoting the pre-nucleation oligomerization of chiral molecules, which consequently regulates the supramolecular chirality of the nanocomposites. We anticipate that this study will aid in rational design of an artificial cooperative system giving rise to emergent assembling phenomena that can be surprisingly rich and often cannot be understood by studying the conventional noncooperative systems.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Yanjun Gong, Zhaozhen Cao, Zongze Zhang, Rongjuan Liu, Fenghua Zhang, Jingjing Wei, Zhijie Yang
onlinelibrary.wiley.com/doi/10.1002/anie.202117406
A new catalytic approach to selective functionalization of the strong C−F bonds in polyfluorinated aliphatic esters and amides is reported, affording a diverse array of important partially fluorinated motifs through hydrodefluorination, defluoroalkylation, and defluoroalkenylation. Straightforward downstream chemistry towards fluorinated alcohols, amines and drug derivatives highlights the potential of the protocol.
Selective C−F bond functionalization of perfluoalkyl units has huge potential towards accessing functionalized organofluorinated compounds, but remains challenging due to the high C−F bond strength and inherent selectivity challenges. We report a new catalytic approach to the selective functionalization of strong C−F bonds in polyfluorinated aliphatic esters and amides. This simple reaction proceeds in mild and operational fashion with divergent conversions, including hydrodefluorination, defluoroalkylation, and defluoroalkenylation, affording a diverse array of important partially fluorinated motifs. Straightforward downstream chemistry towards fluorinated alcohols, amines and drug derivatives highlights the potential of the protocol.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Jian‐Heng Ye, Peter Bellotti, Corinna Heusel, Frank Glorius
onlinelibrary.wiley.com/doi/10.1002/anie.202115456
A strategy based on Bi3+/Te4+ co-doping was developed to achieve dual-band-tunable white-light emission in perovskite-derivative Cs2SnCl6 microcrystals with a quantum yield of up to 68.3 %. Solid evidence including the transition in photoluminescence lifetime from milliseconds at 10 K to microseconds at 300 K was provided to unravel the photoluminescence originating from the inter-configurational 3P0,1→1S0 transitions of Bi3+/Te4+.
Luminescent metal halides have attracted considerable attention in next-generation solid-state lighting because of their superior optical properties and easy solution processibility. Herein, we report a new class of highly efficient and dual-band-tunable white-light emitters based on Bi3+/Te4+ co-doped perovskite derivative Cs2SnCl6 microcrystals. Owing to the strong electron-phonon coupling and efficient energy transfer from Bi3+ to Te4+, the microcrystals exhibited broad dual-band white-light emission originating from the inter-configurational 3P0,1→1S0 transitions of Bi3+ and Te4+, with good stability and a high photoluminescence (PL) quantum yield of up to 68.3 %. Specifically, a remarkable transition in Bi3+-PL lifetime from milliseconds at 10 K to microseconds at 300 K was observed, as solid evidence for the isolated Bi3+ emission. These findings provide not only new insights into the excited-state dynamics of Bi3+ and Te4+ in Cs2SnCl6, but also a general approach to achieve single-composition white-light emitters based on lead-free metal halides through ns2-metal ion co-doping.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Wei Zhang, Wei Zheng, Lingyun Li, Ping Huang, Zhongliang Gong, Ziwei Zhou, Jinyue Sun, Yan Yu, Xueyuan Chen
onlinelibrary.wiley.com/doi/10.1002/anie.202116085
A series of metal-cluster hybrid materials was successfully fabricated by using the electropolymerization (EP) method. Poly-metal clusters in an extended conjugated network establish an electron transport highway to catalytic sites. The improvement in catalytic performance in poly-metal clusters was demonstrated by electrocatalytic reduction of nitrate (NO3−) to ammonia (NH3) and photocatalytic chemical warfare simulant degradation experiments.
Atomically precise metal clusters are attractive as highly efficient catalysts, but suffer from continuous efficiency deactivation in the catalytic process. Here, we report the development of an efficient strategy that enhances catalytic performance by electropolymerization (EP) of metal clusters into hybrid materials. Based on carbazole ligand protection, three polymerized metal-cluster hybrid materials, namely Poly-Cu14cba, Poly-Cu6Au6cbz and Poly-Cu6Ag4cbz, were prepared. Compared with isolated metal clusters, metal clusters immobilizing on a biscarbazole network after EP significantly improved their electron-transfer ability and long-term recyclability, resulting in higher catalytic performance. As a proof-of-concept, Poly-Cu14cba was evaluated as an electrocatalyst for reducing nitrate (NO3−) to ammonia (NH3), which exhibited ≈4-fold NH3 yield rate and ≈2-fold Faraday efficiency enhancement compared to that of Cu14cba with good durability. Similarly, Poly-Cu6Au6cbz showed 10 times higher photocatalytic efficiency towards chemical warfare simulants degradation than the cluster counterpart.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Yi‐Man Wang, Jinmeng Cai, Qian‐You Wang, Yao Li, Zhen Han, Si Li, Chun‐Hua Gong, Shan Wang, Shuang‐Quan Zang, Thomas C. W. Mak
onlinelibrary.wiley.com/doi/10.1002/anie.202114538
Exciton transport plays a pivotal role in organic opto-electronics. Effective triplet energy transfer is difficult to achieve, due to the less efficient Dexter mechanism for triplet exciton transport than Förster resonant energy transfer for singlet exciton transport. Herein, we show that organic PtII and PdII nanowires exhibit long-range triplet exciton diffusion lengths with large diffusion coefficients by metal–metal interaction at room temperature.
Efficient and long-range exciton transport is critical for photosynthesis and opto-electronic devices, and for triplet-harvesting materials, triplet exciton diffusion length () and coefficient () are key parameters in determining their performances. Herein, we observed that PtII and PdII organometallic nanowires exhibit long-range anisotropic triplet exciton LD of 5–7 μm along the M−M direction using direct photoluminescence (PL) imaging technique by low-power continuous wave (CW) laser excitation. At room temperature, via a combined triplet–triplet annihilation (TTA) analysis and spatial PL imaging, an efficient triplet exciton diffusion was observed for the PtII and PdII nanowires with extended close M−M contact, while is absent in nanowires without close M−M contact. Two-dimensional electronic spectroscopy (2DES) and calculations revealed a significant contribution of the delocalized 1/3[dσ*(M−M)→π*] excited state during the exciton diffusion modulated by the M−M distance.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Qingyun Wan, Dian Li, Jiading Zou, Tengfei Yan, Ruidan Zhu, Ke Xiao, Shuai Yue, Xiaodong Cui, Yuxiang Weng, Chi‐Ming Che
onlinelibrary.wiley.com/doi/10.1002/anie.202114323
By programming multi-functional sequences in one ultra-long ssDNA chain and using it as the scaffold, we developed a lysosomal proton-activatable DNA-based nanosystem, which overcomes the countervailing effect of Mn2+ on Cas9 and DNAzyme, and thus achieves efficient co-delivery of CRISPR/Cas9 and DNAzyme for combined gene therapy of breast cancer.
CRISPR/Cas9 is emerging as a platform for gene therapeutics, and the treatment efficiency is expected to be enhanced by combination with other therapeutic agents. Herein, we report a proton-activatable DNA-based nanosystem that enables co-delivery of Cas9/sgRNA and DNAzyme for the combined gene therapy of cancer. Ultra-long ssDNA chains, which contained the recognition sequences of sgRNA in Cas9/sgRNA, DNAzyme sequence and HhaI enzyme cleavage site, were synthesized as the scaffold of the nanosystem. The DNAzyme cofactor Mn2+ was used to compress DNA chains to form nanoparticles and acid-degradable polymer-coated HhaI enzymes were assembled on the surface of nanoparticles. In response to protons in lysosome, the polymer coating was decomposed and HhaI enzyme was consequently exposed to recognize and cut off the cleavage sites, thus triggering the release of Cas9/sgRNA and DNAzyme to regulate gene expressions to achieve a high therapeutic efficacy of breast cancer.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Feng Li, Nachuan Song, Yuhang Dong, Shuai Li, Linghui Li, Yujie Liu, Zhemian Li, Dayong Yang
onlinelibrary.wiley.com/doi/10.1002/anie.202116569
Controlled thermal treatment of the common decavanadate cluster in the solid state yields a universal precursor for the synthesis of large, metal-functionalized polyoxovanadates, as demonstrated for three examples.
Molecular metal oxides are key materials in diverse fields like energy storage and conversion, molecular magnetism and as model systems for solid-state metal oxides. To improve their performance and increase the variety of accessible motifs, new synthetic approaches are necessary. Herein, we report a universal, new precursor to access different metal-functionalized polyoxovanadate (POV) clusters. The precursor is synthesized by a novel solid-state thermal treatment procedure. Solution-phase test reactions at room temperature and pressure show that reaction of the precursor with various metal nitrate salts gives access to a range of metal-functionalized POVs. The first nitrate-templated molecular calcium vanadate cluster is reported. We show that this precursor could open new access routes to POV components for molecular magnetism, energy technologies or catalysis.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Simon Greiner, Jan Hettig, Alec Laws, Katharina Baumgärtner, Jenna Bustos, Ann‐Christin Pöppler, Adam H. Clark, May Nyman, Carsten Streb, Montaha Anjass
onlinelibrary.wiley.com/doi/10.1002/anie.202114548
A unique uranyl-triggered photocleavage property is used for uranyl detection in diverse environments. This method is characterized by ultrasensitive detection, a wide detection range, as well as extensive environmental adaptability and is among the best-performing uranyl detection methods.
The detection of environmental uranyl is attracting increasing attention. However, the available detection strategies mainly depend on the selective recognition of uranyl, which is subject to severe interference by coexisting metal ions. Herein, based on the unique uranyl-triggered photocleavage property, the protein BSA is labelled with fluorescent molecules that exhibit an aggregation-induced emission effect for uranyl detection. Uranyl-triggered photocleavage causes the separation of the fluorescent-molecule-labelled protein fragments, leading to attenuation of the emission fluorescence, which is used as a signal for uranyl detection. This detection strategy shows high selectivity for uranyl and an ultralow detection limit of 24 pM with a broad detection range covering five orders of magnitude. The detection method also shows high reliability and stability, making it a promising technique for practical applications in diverse environments.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Tiantian Feng, Yihui Yuan, Shilei Zhao, Lijuan Feng, Bingjie Yan, Meng Cao, Jiacheng Zhang, Wenyan Sun, Ke Lin, Ning Wang
onlinelibrary.wiley.com/doi/10.1002/anie.202115886
Replacing the benzene ring in the rhodamine core with a permanently charged 1,3-disubstituted imidazolium markedly improves the photoswitching behavior and overall performance of (direct) stochastic optical reconstruction microscopy ((d)STORM). Excellent super-resolution microscopy images are thus obtained under green excitation.
We introduce a strategy to optimize the photoswitching behavior of rhodamines for (d)STORM super-resolution microscopy. By replacing the benzene ring in the rhodamine core with a permanently charged 1,3-disubstituted imidazolium, the resultant dyes are markedly sensitized toward photoswitching, and exhibit outstanding (d)STORM performance with fast on-off switching, long-lasting blinking, and bright single-molecule emission. We thus attain excellent (d)STORM images under green excitation that are on par with the “ideal” red-excited dyes, including for difficult structures such as the mammalian actin cytoskeleton, and demonstrate high-quality two-color three-dimensional (d)STORM.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Bowen Wang, Michael Xiong, Josephine Susanto, Xue Li, Wai‐Yee Leung, Ke Xu
onlinelibrary.wiley.com/doi/10.1002/anie.202113612
Compared to typical linear conjugated material (Y6), the two-dimensional polycyclic material TPP designed and synthesized here exhibits much lower trap density. The bulk heterojunction nanoparticles based on a blend of polymer donor and TPP, exhibited an enhanced average hydrogen evolution rate of 72.75 mmol h−1 g−1 under 330 to 1100 nm illumination, which is 2–3 orders of magnitude higher than those values of inorganic/hybrid photocatalysts.
Typical organic semiconductors show a high trap density of states (1016–1018 cm−3), providing a large number of centers for charge-carrier recombination, thus hindering the development of photocatalytic hydrogen evolution. Here, we design and synthesize a two-dimensional polycyclic photovoltaic material, named as TPP, to reduce the trap density to as low as 2.3×1015 cm−3, which is 1–3 orders of magnitude lower than those of typical organic semiconductors. Moreover, TPP exhibits a broad and strong absorption, ordered molecular packing with a large crystalline coherence length and enhanced electron mobility. Then, the bulk heterojunction nanoparticles (BHJ-NPs) based on a blend of polymer donor (PM6) and TPP exhibit an average hydrogen evolution rate (HER) of 64.31 mmol h−1 g−1 under AM1.5G sunlight (100 mW cm−2), and 72.75 mmol h−1 g−1 under 330–1100 nm illumination (198 mW cm−2) higher than that of the control NPs based on typical PM6 : Y6 (62.67 mmol h−1 g−1).
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Zhenzhen Zhang, Wenqin Si, Baohua Wu, Wei Wang, Yawen Li, Wei Ma, Yuze Lin
onlinelibrary.wiley.com/doi/10.1002/anie.202114234
A concept of acid-orthogonal deprotection chemistry which proceed independently of one another by the selection of protecting groups that feature the respective acid-lability is reported. This chemistry increases the compatibility with otherwise sensitive groups and opens up pathways to facilely introduce structural and functional diversity into stereo- and sequence-defined polymers.
Absolute control over polymer stereo- and sequence structure is highly challenging in polymer chemistry. Here, an acid-orthogonal deprotection strategy is proposed for the iterative synthesis of a family of unimolecular polymers starting with enantiopure serines, featuring precise sequence, stereoconfiguration and side-chain functionalities that cannot be achieved using traditional polymerization techniques. Acid-orthogonal deprotections proceed independently of one another by the selection of protecting groups that feature the respective acid-lability. Under p-toluenesulfonic acid, acidolysis of tert-butyloxycarbonyl can proceed exclusively, while low-dosage trifluoroacetic acid and low temperature only trigger the selective and quantitative cleavage of trityl. The pioneering use of this acid-orthogonal deprotection chemistry increases the compatibility with otherwise sensitive groups and opens up pathways to facilely introduce structural and functional diversity into stereo- and sequence-defined polymers, thus imparting their unique properties beyond natural biopolymers.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Wenjing He, Shixue Wang, Maosheng Li, Xianhong Wang, Youhua Tao
onlinelibrary.wiley.com/doi/10.1002/anie.202112439
The first ternary halogen-rich nonlinear optical chalcohalide Sn7Br10S2 exhibits a strong phase-matchable second-harmonic generation response (1.5 × AGS@2.1 μm) and high laser-induced damage threshold (6.3 × AGS). This work provides a competitive candidate with good performance, facile synthesis and simple chemical composition for infrared nonlinear optical (IR NLO) applications, and also introduces a facile strategy to obtain high-performance NLO materials via a symmetry break.
Infrared nonlinear optical (IR NLO) materials are significant in laser technology for civil and military uses. Here, we report the synthesis, structural chemistry and NLO properties of a halogen-rich chalcohalide Sn7Br10S2. Its noncentrosymmetric (NCS, P63) structure can be considered as partially aliovalent anion substitution of SnBr2 (P63/m) induced centrosymmetric (CS) to NCS structural transformation. The 3D∞[Sn(1)6Sn(2)6Br6X6]6− (X=Br/S) channel framework consists of Sn(1)BrX2 and Sn(2)X3 trigonal pyramids. It exhibits excellent NLO performance, including a strong phase-matchable NLO response of 1.5 × AgGaS2and high laser-induced damage threshold of 6.3 × AgGaS2.Investigation of the structure–NLO performance relationship confirms that the effective arrangement of Sn(1)BrX2 and Sn(2)X3 units predominantly contributes to the large SHG response. These results indicate Sn7Br10S2 is a potential IR NLO candidate and provides a new feasible system for promising NLO materials.
Wiley: Angewandte Chemie International Edition: Table of Contents
Authors: Xiao‐Hui Li, Zhi‐Hui Shi, Mei Yang, Wenlong Liu, Sheng‐Ping Guo
onlinelibrary.wiley.com/doi/10.1002/anie.202115871
The Journal of Organic Chemistry: Latest Articles (ACS Publications)
Authors: Shinya Shiomi, Kaewsri Wilailak, Wataru Soutome, Hiromitsu Takayama, Mariko Kitajima, and Hayato Ishikawa
dx.doi.org/https://doi.org/10.1021/acs.joc.1c02672
![Synthesis, crystal structure, and DFT study of 4-(2-Chlorobenzyl)-1-(furan-2-yl)-[1,2,4]triazolo[4,3-a]quinazolin-5(4H)-one](https://d-bernier.fr/wp-content/uploads/2022/01/jhet4373-toc-0001-m.png)
4-(2-Chlorobenzyl)-1-(furan-2-yl)-[1,2,4]triazolo[4,3-a]quinazolin-5(4H)-one is a triazoloquinazolinone compound with broad-spectrum biological activity. In this study, the four-step method was used to synthesize the title compound, and its structure was confirmed by Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H NMR), 13-carbon nuclear magnetic resonance (13C NMR) spectroscopy, and mass spectroscopy (MS). Further, its single crystal was characterized by X-ray diffraction. The density functional theory was used to calculate the optimal structure of the molecule. The results demonstrated that the analyzed structure was consistent with the crystal structure determined by single-crystal diffraction. In addition, discrete Fourier transform was used to study the molecular electrostatic potential and Frontier molecular orbital of the title compound, revealing a few of the compound’s physicochemical properties.
ACS Medicinal Chemistry Letters: Latest Articles (ACS Publications)
Authors: Ram W. Sabnis
dx.doi.org/http://dx.doi.org/10.1021/acsmedchemlett.1c00724
