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501.
Dr. Changhua Song Dr. Fang Zheng Dr. Ying Liu Prof. Qiwei Yang Prof. Zhiguo Zhang Prof. Qilong Ren Prof. Zongbi Bao 《Angewandte Chemie (International ed. in English)》2023,62(51):e202313855
The one-step purification of ethylene (C2H4) from mixtures containing ethane (C2H6) and acetylene (C2H2) is an industrially important yet challenging process. In this work, we present a site-engineering strategy aimed at manipulating the spatial distribution of binding sites within a confined pore space. We realized successfully by incorporating nitrogen-containing heterocycles, such as indole-5-carboxylic acid (Ind), benzimidazole-5-carboxylic acid (Bzz), and indazole-5-carboxylic acid (Izo), into the robust MOF-808 platform via post-synthetic modification. The resulting functionalized materials, namely MOF-808-Ind, MOF-808-Bzz, and MOF-808-Izo, demonstrated significantly improved selectivity for C2H2 and C2H6 over C2H4. MOF-808-Bzz with two uniformly distributed nitrogen binding sites gave the optimal geometry for selective ethane trapping through multiple strong C−H⋅⋅⋅N hydrogen bonds, leading to the highest C2H2/C2H4 and C2H6/C2H4 combined selectivities among known MOFs. Column breakthrough experiments validated its ability to purify C2H4 from ternary C2H2/C2H4/C2H6 mixtures in a single step. 相似文献
502.
Dr. Ben Ma Qi Xia Deyang Wang Dr. Ji-Kang Jin Zekun Li Qiu-Jiang Liang Meng-Ying Sun Dongyi Liu Li-Juan Liu Dr. Hui-Xing Shu Prof. Dr. Jun Yang Prof. Dr. Dan Li Prof. Dr. Jian He 《Angewandte Chemie (International ed. in English)》2023,62(21):e202304253
Visible-light copper photocatalysis has recently emerged as a viable technology for building sustainable synthetic processes. To broaden the applications of phosphine-ligated copper(I) complexes, we describe herein an effective metal-organic framework (MOF)-supported copper(I) photocatalyst for multiple iminyl radical-mediated reactions. Due to site isolation, the heterogenized copper photosensitizer has a significantly higher catalytic activity than its homogeneous counterpart. Using a hydroxamic acid linker to immobilize copper species on MOF supports affords the heterogeneous catalysts with high recyclability. The post-synthetic modification sequence on MOF surfaces allows for the preparation of previously unavailable monomeric copper species. Our findings highlight the potential of using MOF-based heterogeneous catalytic systems to address fundamental challenges in the development of synthetic methodologies and mechanistic investigations of transition-metal photoredox catalysis. 相似文献
503.
Wenlong Xie Dr. Fuming Li Jianbang Chen Prof. Zhihuang Yang Dr. Guangmao Li Prof. Shilie Pan 《Angewandte Chemie (International ed. in English)》2023,62(34):e202307895
Performance enhancement induced by structural modification has long been the target in materials science fields. Direct evidence to witness the effectivity of one strategy is challenging and necessary. In this work, a tetrahedra-decoration strategy was proposed to improve the birefringent performance sharply, namely decorating the tetrahedra with a single linear [S2] unit. The strategy was verified by comprehensive characterization of two thiogermanates K2BaGeS4 and K2BaGeS5, which crystallize in the same space group, have similar unit cells and the same units arrangements. Theoretical characterization verified that the [GeS5] group has much larger polarization anisotropy than [GeS4], further demonstrated that the linear [S2] led to the sharp birefringence enlargement of K2BaGeS5 (0.19 vs 0.03 of K2BaGeS4). This work provides a new guiding thought to improve the birefringence performance. 相似文献
504.
Matthias Frese Philip Saumer Yizhi Yuan Doreen Herzog Dorothea Höpfner Prof. Dr. Aymelt Itzen Prof. Dr. Andreas Marx 《Angewandte Chemie (International ed. in English)》2023,62(8):e202213279
Diadenosine polyphosphates (ApnAs) are non-canonical nucleotides whose cellular concentrations increase during stress and are therefore termed alarmones, signaling homeostatic imbalance. Their cellular role is poorly understood. In this work, we assessed ApnAs for their usage as cosubstrates for protein AMPylation, a post-translational modification in which adenosine monophosphate (AMP) is transferred to proteins. In humans, AMPylation mediated by the AMPylator FICD with ATP as a cosubstrate is a response to ER stress. Herein, we demonstrate that Ap4A is proficiently consumed for AMPylation by FICD. By chemical proteomics using a new chemical probe, we identified new potential AMPylation targets. Interestingly, we found that AMPylation targets of FICD may differ depending on the nucleotide cosubstrate. These results may suggest that signaling at elevated Ap4A levels during cellular stress differs from when Ap4A is present at low concentrations, allowing response to extracellular cues. 相似文献
505.
506.
Xin Zhao Yan Chen Bo Peng Jia Wei Yanlei Yu 《Angewandte Chemie (International ed. in English)》2023,62(21):e202300699
Post-polymerization modification (PPM) offers a versatile approach for engineering multifunctional polymers, but this advantage has not been fully exploited to fabricate multifunctional liquid crystal polymers (LCPs). Here, we design a facile synthetic approach towards multifunctional LCP by combining the ring-opening metathesis polymerization (ROMP) with PPM, in which ROMP helps to prepare a reactive LCP precursor with high molecular weight, and PPM provides a facilitation to introduce functional groups into the precursor. Consequently, a photo- and humidity-responsive linear LCP (LLCP) is demonstrated to show the potential of this synthetic strategy to diversify functions of the LCPs. Under light irradiation and humidity changes, the deformation modes of the LLCP films are converted to complex shapes (bending, twisting, and curling). The obtained dual-responsive LLCP with high molecular weight possesses excellent processability and recyclability, making it possible to construct 3D shape actuators with programmable deformation behaviors under light/humidity. 相似文献
507.
Dr. Hai-Ning Zhang Prof. Dr. Guo-Xin Jin 《Angewandte Chemie (International ed. in English)》2023,62(46):e202313605
By exploiting coordination-driven self-assembly, high yields of two 818 molecular metalla-knots could be obtained using a thiazole-moiety-containing asymmetric dipyridyl ligand 2-(pyridin-4-yl)-5-(pyridin-4-ylethynyl)benzo[d]thiazole ( L1 ), as confirmed using X-ray crystallographic analysis, electrospray ionization-time-of-flight/mass spectrometry (ESI-TOF/MS), and detailed liquid-state nuclear magnetic resonance (NMR) spectroscopy. To modulate the self-assembled structures, m-chloroperbenzoic acid (m-CPBA) was utilized to oxidize thiazole-based ligand L1 to N-thiazole-oxide-based ligand 2-(pyridin-4-yl)-5-(pyridin-4-ylethynyl)benzo[d]thiazole 3-oxide ( L2 ), which enabled the selective construction of the corresponding tetranuclear macrocycles. Notably, two molecular metalla-knots could be topologically transformed from 818 knots to simple monocycles because the L1 alkyne bond was inert toward m-CPBA, as confirmed by liquid-state NMR spectroscopy, ESI-TOF/MS, and elemental analysis. 相似文献
508.
Dr. Guang-Hui Chen Yan-Ping He Yinghua Yu Hong Lv Dr. Shangda Li Prof. Fei Wang Prof. Zhi-Gang Gu Prof. Jian Zhang 《Angewandte Chemie (International ed. in English)》2023,62(16):e202300726
A chiral metal–organic cage (MOC) was extended and fixed into a porous framework using a post-assembly modification strategy, which made it easier to study the host–guest chemistry of the solid-state MOC using a single-crystal diffraction technique. Anionic Ti4L6 (L=embonate) cage can be used as a 4-connecting crystal engineering tecton, and its optical resolution was achieved, thus homochiral ΔΔΔΔ- and ΛΛΛΛ-[Ti4L6] cages were obtained. Accordingly, a pair of homochiral cage-based microporous frameworks ( PTC-236(Δ) and PTC-236(Λ) ) were easily prepared by a post-assembly reaction. PTC-236 has rich recognition sites provided by the Ti4L6 moieties, chiral channels and high framework stability, affording a single-crystal-to-single-crystal transformation for guest structure analyses. Thus it was successfully utilized for the recognition and separation of isomeric molecules. This study provides a new approach for the orderly combination of well-defined MOCs into functional porous frameworks. 相似文献
509.
Dr. Shujian Rong Dr. Mengshi Wang Prof. Dr. Xun Wang 《Angewandte Chemie (International ed. in English)》2023,62(38):e202310018
Two-dimensional (2D) AIE-inorganic nanocomposites exhibit high stability and high fluorescence activity. However, limited by the types and properties of 2D inorganic materials, it's challenging to realize complex structures and functions. We designed a quaternary ammonium-type AIE ligand, TPECholine. We chose TPECholine and POM clusters as building blocks and synthesized a series of single-layer nanosheets (SLNSs) by assembling LnW10 or P2W18 POM clusters with TPECholine. By regulating the types of POM clusters and ligands, the morphology and fluorescence intensity of the SLNSs can be finely tuned. Due to the restriction of the intramolecular motions of AIEgens by the SLNSs, nanosheets can exhibit promoted quantum yield (up to 76 %). In addition, thanks to the sub-nanometric sizes and excess surface charges, SLNSs exhibit excellent solvent compatibility, including water, chloroform, ethanol, etc. And the nanosheets showed high fluorescence intensity in these solvents. 相似文献
510.
Dr. Alessandro Colombano Dr. Luca Dalponte Dr. Sergio Dall'Angelo Claudia Clemente Dr. Mohannad Idress Ahmad Ghazal Dr. Wael E. Houssen 《Angewandte Chemie (International ed. in English)》2023,62(16):e202215979
Aromatic prenyltransferases from cyanobactin biosynthetic pathways catalyse the chemoselective and regioselective intramolecular transfer of prenyl/geranyl groups from isoprene donors to an electron-rich position in these macrocyclic and linear peptides. These enzymes often demonstrate relaxed substrate specificity and are considered useful biocatalysts for structural diversification of peptides. Herein, we assess the isoprene donor specificity of the N1-tryptophan prenyltransferase AcyF from the anacyclamide A8P pathway using a library of 22 synthetic alkyl pyrophosphate analogues, of which many display reactive groups that are amenable to additional functionalization. We further used AcyF to introduce a reactive moiety into a tryptophan-containing cyclic peptide and subsequently used click chemistry to fluorescently label the enzymatically modified peptide. This chemoenzymatic strategy allows late-stage modification of peptides and is useful for many applications. 相似文献