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Lei Z, Zhao P, Guan ZJ, Nan ZA, Ehara M, Wang QM. 'Passivated Precursor' Approach to All-Alkynyl-Protected Gold Nanoclusters and Total Structure Determination of Au130. Chemistry 2024:e202401094. [PMID: 38797717 DOI: 10.1002/chem.202401094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Revised: 05/15/2024] [Accepted: 05/24/2024] [Indexed: 05/29/2024]
Abstract
A 'passivated precursor' approach is developed for the efficient synthesis and isolation of all-alkynyl-protected gold nanoclusters. Direct reduction of dpa-passivated precursor Au-dpa (Hdpa = 2,2'-dipyridylamine) in one-pot under ambient conditions gives a series of clusters including Au22(C≡CR)18 (R = -C6H4-2-F), Au36(C≡CR)24, Au44(C≡CR)28, Au130(C≡CR)50, and Au144(C≡CR)60. These clusters can be well separated via column chromatography. The overall isolation yield of this series of clusters is 40% (based on gold), which is much improved in comparison with previous approaches. It is notable that the molecular structure of the giant cluster Au130(C≡CR)50 is revealed, which presents important information for understanding the structure of the mysterious Au130 nanoclusters. Theoretical calculations indicated Au130(C≡CR)50 has a smaller HOMO-LUMO gap than Au130(S-C6H4-4-CH3)50. This facile and reliable synthetic approach will greatly accelerate further studies on all-alkynyl-protected gold nanoclusters.
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Yang Y, Guo S, Zhang Q, Guan ZJ, Wang QM. A Cages-on-Cluster Structure Constructed by Post-Clustering Covalent Modifications and Guest-Enabled Stimuli-Responsive Luminescence. Angew Chem Int Ed Engl 2024:e202404798. [PMID: 38713516 DOI: 10.1002/anie.202404798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 05/07/2024] [Accepted: 05/07/2024] [Indexed: 05/09/2024]
Abstract
A novel gold(I)-cluster-based twin-cage is constructed by post-clustering covalent modification of a hexa-aldehyde cluster precursor with triaminotriethylamines. The cages-on-cluster structure have double cavities and four binding sites, showing site discriminative binding for silver(I) and copper(I) guests. The guests in the tripodal hats affect the luminescence of the cluster: tetra-silver(I) host-guest complex is weak red emissive, while bis-copper(I)-bis-silver(I) one is non-emissive but a stimuli-responsive supramolecule. The copper(I) ion inside the tri-imine cavity is oxidation sensitive, which enable the release of the bright emissive precursor cluster triggered by H2O2 solution. The hybridization of a cluster with cavities to construct a cluster-based cage presents an innovative concept for functional cluster design, and the post-clustering covalent modification opens up new avenues of finely tuning the properties of clusters.
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Pei XL, Ma C, Guan ZJ, Ni SF, Wang QM. Heterometallic Au I 6 Ag I 6 Macrocyclic Cluster Templated by a Supramolecular Melamine Dimer. Chemistry 2024; 30:e202301948. [PMID: 38081801 DOI: 10.1002/chem.202301948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Indexed: 01/13/2024]
Abstract
The application of supramolecular templates in aligning atomically precise heterometal arrays is important for pursuing functional materials. Herein, we report that a bilayered supramolecular tri-deprotonated melamine dimer functions as an effective template in the construction of a heterometallic gold(I)-silver(I) macrocyclic cluster [μ6 -(C3 N6 H3 )3- ]2 -AuI 6 AgI 6 . X-ray single crystal structural analysis showed that a crown-like AuI 6 AgI 6 macrocycle is aligned around two parallelly stacked μ6 -(C3 N6 H3 )3- moieties hold together with π-π interactions. Theoretical calculations revealed that the [μ6 -(C3 N6 H3 )3- ]2 motif dominantly contributes to the near-occupied orbitals in the electronic structure, which is closely related to its luminescence properties. This work demonstrates that the supramolecular templates containing multiple symmetric binding sites may present a facile approach in the construction of functional metal clusters.
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Hu F, Guan ZJ, Yuan SF, Wang QM. Alkynyl-Protected Bimetallic Nanoclusters with a Hybrid Mackay Icosahedral Ag 42 Cu 12 Cl Kernel and an Octahedral Ag 22 Cu 12 Kernel. Chem Asian J 2023; 18:e202300605. [PMID: 37550250 DOI: 10.1002/asia.202300605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/07/2023] [Accepted: 08/07/2023] [Indexed: 08/09/2023]
Abstract
A facile strategy that directly reduces alkynyl-silver precursors and copper salts for the synthesis of bimetallic nanoclusters using the weak reducing agent Ph2 SiH2 is demonstrated. Two alkynyl-protected concentric-shell nanoclusters, (Ph4 P)2 [Ag22 Cu12 (C≡CR)28 ] and (Ph4 P)3 [Ag42 Cu12 Cl(C≡CR)36 ] (Ag22 Cu12 and Ag42 Cu12 Cl, R=bis(trifluoromethyl)phenyl), were successfully obtained and characterized by single-crystal X-ray diffraction and electro-spray ionization mass spectrometry. For the first time, a hybrid 55-atom two-shell Mackay icosahedron was found in Ag42 Cu12 Cl, which is icosahedral M54 Cl instead of M55 . The incorporation of a chloride in the metal icosahedron contributes to the stability of the cluster from both electronic and geometric aspects. Alkynyl ligands show various binding-modes including linear "RC≡C-Cu-C≡CR" staple motifs.
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Wang JQ, He RL, Liu WD, Feng QY, Zhang YE, Liu CY, Ge JX, Wang QM. Integration of Metal Catalysis and Organocatalysis in a Metal Nanocluster with Anchored Proline. J Am Chem Soc 2023. [PMID: 37246940 DOI: 10.1021/jacs.3c02567] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Chiral metal nanoclusters have recently been attracting great attention. It is challenging to realize asymmetric catalysis via atomically precise metal nanoclusters. Herein, we report the synthesis and total structure determination of chiral clusters [Au7Ag8(dppf)3(l-/d-proline)6](BF4)2 (l-/d-Au7Ag8). Superatomic clusters l-/d-Au7Ag8 display intense and mirror-image Cotton effects in their CD spectra. Density functional theory (DFT) calculations were carried out to understand the correlation between electronic structures and the optical activity of the enantiomeric pair. Surprisingly, the incorporation of proline in a metal nanocluster can significantly promote the catalytic efficiency in asymmetric Aldol reactions. The increase of catalytic activity of Au7Ag8 in comparison with organocatalysis by proline is attributed to the cooperative effect of the metal core and prolines, showing the advantages of the integration of metal catalysis and organocatalysis in a metal nanocluster.
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Hu F, He RL, Guan ZJ, Liu CY, Wang QM. Disc-like Silver Nanocluster Ag93 Built with Bicapped Hexagonal Prismatic Ag15 and Ino Decahedral Ag13 Units. Angew Chem Int Ed Engl 2023:e202304134. [PMID: 37211537 DOI: 10.1002/anie.202304134] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 05/23/2023]
Abstract
The reduction of alkynyl-silver and phosphine-silver precursors with a weak reducing reagent Ph2SiH2 led to the formation of a novel silver nanocluster [Ag93(PPh3)6(C≡CR)50]3+ (R = 4-CH3OC6H4), which is the largest structurally characterized cluster of clusters. This disc-shaped cluster has a Ag69 kernel consisting of a bicapped hexagonal prismatic Ag15 wrapped by six Ino decahedral through edge-sharing. This is the first time to observe that Ino decahedra can be used as building blocks to assemble a cluster of clusters. Moreover, the central silver atom has a coordination number of 14, which is the highest in metal nanoclusters. This work provides a diverse metal packing pattern in metal nanoclusters, which is helpful for the understanding of metal cluster assembling mechanisms.
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Guan ZJ, Li JJ, Hu F, Wang QM. Structural Engineering toward Gold Nanocluster Catalysis. Angew Chem Int Ed Engl 2022; 61:e202209725. [PMID: 36169269 DOI: 10.1002/anie.202209725] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Indexed: 12/14/2022]
Abstract
Atomically precise gold nanoclusters provide great opportunities to explore the relationship between the structure and properties of nanogold catalysts. A nanocluster consists of a metal core and a surface ligand shell, and both the core and shell have significant effects on the catalytic properties. Thanks to their precise structures, the active metal site of the clusters can be readily identified and the effects of ligands on catalysis can be disclosed. In this Minireview, we summarize recent advances in catalytic research of gold nanoclusters, emphasizing four strategies for constructing open metal sites, including by post-treatment, the bulky ligands strategy, the surface geometric mismatch method, and heteroatom doping procedures. We also discuss the effects of ligands on the catalytic activity, selectivity, and stability of gold cluster catalysts. Finally, we present future challenges relating to gold cluster catalysis.
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Hu F, Luyang HW, He RL, Guan ZJ, Yuan SF, Wang QM. Face-Centered Cubic Silver Nanoclusters Consolidated with Tetradentate Formamidinate Ligands. J Am Chem Soc 2022; 144:19365-19371. [PMID: 36227067 DOI: 10.1021/jacs.2c07018] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Growing attention has been paid to nanoclusters with face-centered cubic (fcc) metal kernels, due to its structural similarity to bulk metals. We demonstrate that the use of tetradentate formamidinate ligands facilitate the construction of two fcc silver nanoclusters: [Ag52(5-F-dpf)16Cl4](SbF6)2 (Ag52, 5-F-Hdpf = N,N'-di(5-fluoro-2-pyridinyl)formamidine) and [Ag53(5-Me-dpf)18](NO3)5 (Ag53, 5-Me-Hdpf = N,N'-di(5-methyl-2-pyridinyl)formamidine). Single-crystal X-ray structural analysis revealed that the silver atoms in both clusters are in a layer-by-layer arrangement, which can be viewed as a portion of the fcc packing of silver. The nitrogen donors of amidinate ligands selectively passivate the {111} facets. All silver atoms are involved in the fcc packing, that is, no staple motifs are observed due to the linear arrangement of the four N donors of the dpf ligands. The characteristic optical absorption bands of Ag52 and Ag53 have been studied with a time-dependent density functional theory. This work provides a facile access to assembling atomically precise fcc-type nanoclusters and shows the prospect of amidinates as protecting ligands in synthesizing metal nanoclusters.
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Guan ZJ, Li JJ, Hu F, Wang QM. Structural Engineering toward Gold Nanocluster Catalysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Yuan SF, Guan ZJ, Wang QM. Identification of the Active Species in Bimetallic Cluster Catalyzed Hydrogenation. J Am Chem Soc 2022; 144:11405-11412. [PMID: 35700103 DOI: 10.1021/jacs.2c04156] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Identification of the authentic active species of cluster catalysis is rather challenging, and direct structural evidence is quite valuable and difficult to obtain. Two "isostructural" clusters, Ag25Cu4Cl6(dppb)6(PhC≡C)12(SO3CF3)3 (1) and Ag25Cu4Cl6H8(dppb)6(PhC≡C)12(SO3CF3)3 (2H) (dppb is 1,4-bis(diphenylphosphine)butane), have been successfully isolated and structurally characterized. Both these clusters have a centered icosahedron Ag13 core with the same peripheral composition and structure. The only difference is that 2H has eight hydrides but 1 has none, that is, the kernels are Ag135+ and Ag13H85+ in 1 and 2H, respectively. The catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) as a model reaction is assessed with the two clusters. Cluster 2H is very active with 100% yield within 2 h, whereas 1 shows a very low conversion (∼8%) under the same conditions. Interestingly, high catalytic activity was observed when 1 was converted to 2H with the oxidation of H2O2 under catalytic conditions. The unprecedented transformation of a reduced nanocluster to an Ag(I)Cu(I) bimetallic cluster compound provides an excellent platform to determine the real active cluster in terms of metal cluster catalysis. The present work presents clear structural evidence that the catalytic performance of metal nanoclusters can be modulated by properly regulating the oxidation state of their constituted metal atoms.
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Chen YC, Wang QM, Chen L, Zhu MH, Zhang J. [Arf6 regulates endometriotic epithelial-mesenchymal transition and mitochondrial distribution]. ZHONGHUA FU CHAN KE ZA ZHI 2022; 57:442-448. [PMID: 35775252 DOI: 10.3760/cma.j.cn112141-20220126-00050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To investigate the role of adenosine diphosphate ribosylation factor 6 (Arf6) in the pathogenesis of endometriosis. Methods: Endometrial tissues were sampled from women who were hospitalized in the Affiliated Hospital of Medical School of Ningbo University and Ningbo Women and Children's Hospital from November 2020 to May 2021 with endometriosis (n=44, endometriosis group) and without endometriosis (n=17, control group). The expression of Arf6 protein in the endometrial tissues was detected by western blot. Endometrial epithelial cells from both groups were primary cultured and the distribution of intracellular mitochondria was detected by immunofluorescence. The expression of Arf6 protein was down-regulated by small interference RNA (siRNA), the distribution of mitochondria in cells with decreased Arf6 protein expression was observed, and the expression of mitochondria-related proteins development and differentiation enhancing factor 1 (DDEF1, also called AMAP1), reactive oxygen species 1 (ROS1) and epithelial-mesenchymal transition (EMT)-related proteins E-cadherin, vimentin were detected. Transwell assay was used to detect the changes in the migration ability of the cells. Results: Compared with the control group, ectopic endometrial tissue of endometriosis group showed high expression of Arf6 protein (0.174±0.019 vs 0.423±0.033; t=29.630, P<0.01); and in ectopic endometrial epithelial cells, mitochondria were distributed near the edge of the cell membrane. While Arf6 expression was down-regulated by siRNA, the distribution of mitochondria in ectopic cells returned to natural, close to the control level. In addition, the expression levels of AMAP1 and ROS1 in ectopic cells after Arf6 protein knockdown were significantly decreased. Transwell assay results indicated that knockdown of Arf6 could reduce the migration ability of ectopic epithelial cells [migration cell count: (34.3±7.5) cells]; and immunofluorescence verified low expression of E-cadherin but high expression of vimentin in ectopic epithelial cells, whereas knockdown of Arf6 protein E-cadherin expression increased but vimentin expression decreased. Conclusions: High expression of Arf6 protein in ectopic endometrial epithelial cells leads to the distribution of mitochondria tending to membrane marginalization, while inducing EMT, which are involved in the mechanism of endoheterosis pathogenesis.
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Li JJ, Liu CY, Guan ZJ, Lei Z, Wang QM. Anion-Directed Regulation of Structures and Luminescence of Heterometallic Clusters. Angew Chem Int Ed Engl 2022; 61:e202201549. [PMID: 35393719 DOI: 10.1002/anie.202201549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Indexed: 11/09/2022]
Abstract
Anions have been used to regulate the structures and luminescence of heterometallic clusters. Introducing ClO4 - into orange-emissive, butterfly-like [(C)(Au-PPhpy2 )6 Ag4 ](BF4 )6 (1, PPhpy2 =bis(2-pyridyl)phenylphosphine) leads to the formation of red-emissive [(C)(Au-PPhpy2 )6 Ag5 (ClO4 )3 ](ClO4 )4 (2) with a novel trigonal bipyramidal structure; employing PhCO2 - gives yellow-emissive, hexagram-like [(C)(Au-PPhpy2 )6 Ag6 (PhCO2 )3 ](BF4 )5 (3). Notably, 1 exhibits weak luminescence in CH2 Cl2 /CH3 OH=1 : 1 (v : v) with a quantum yield (QY) of 0.05, whereas it was dramatically increased to 0.49 and 0.83 for 2 and 3, respectively. Theoretical calculation confirms that the involvement of anions in the electronic structures is responsible for the shifts of emission. The high QYs of 2 and 3 are attributed to the protection provided by ligands and anions. This work demonstrates that anions may serve as an extra designable factor beyond just counterions for functional metal clusters.
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Yang N, Zhao W, Pan Y, Lyu XZ, Hao XY, Qi WA, Du L, Liu EM, Chen T, Zhang WS, Zhang CF, Zhu GN, Wang QM, Meng WB, Liang YB, Jin YH, Wang W, Xing D, Tian JH, Ma B, Wang XH, Song XP, Ge L, Yang KH, Liu XQ, Wei JM, Chen Y. [Development of a Ranking Tool for Scientificity, Transparency and Applicability of Clinical Practice Guidelines]. ZHONGHUA YI XUE ZA ZHI 2022; 102:1-10. [PMID: 35701091 DOI: 10.3760/cma.j.cn112137-20220219-00340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To address the limitations of existing methods and tools for evaluating clinical practice guidelines, we aimed to develop a comprehensive instrument focusing on the three main dimensions of guideline development: scientificity, transparency, applicability. We will use it to rank the guidelines according to the scores. We abbreviated it as STAR, and its reliability, validity and usability were also tested. Methods: A multidisciplinary expert working group was set up, including methodologists, statisticians, journal editors, medical professionals, and others. Scoping review, Delphi methods and hierarchical analysis were used to determine the final checklist of STAR. Results: The new instrument contained 11 domains and 39 items. Intrinsic reliability of each domain was indicated by Cronbach's α coefficient, with a average value of 0.646. The Cohen's kappa coefficients for methodological evaluators and clinical evaluators were 0.783 and 0.618. The overall content validity index was 0.905. The R2 for the criterion validity analysis was 0.76. The average score for usability of the items was 4.6, and the mean time spent to evaluate each guideline was 20 minutes. Conclusion: The instrument has good reliability, validity and evaluating efficiency, and can be used for evaluating and ranking guidelines more comprehensively.
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Yuan SF, Liu WD, Liu CY, Guan ZJ, Wang QM. Nitrogen Donor Protection for Atomically Precise Metal Nanoclusters. Chemistry 2022; 28:e202104445. [PMID: 35218267 DOI: 10.1002/chem.202104445] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Indexed: 12/21/2022]
Abstract
Surface organic ligands are critical in dictating the structures and properties of atomically precise metal nanoclusters. In contrast to the conventionally used thiolate, phosphine and alkynyl ligands, nitrogen donor ligands have not been used in the protection for well-defined metal nanoclusters until recently. This review focuses on recent developments in atomically precise metal nanoclusters stabilized by different types of nitrogen donor ligands, in which the synthesis, total structure determination and various properties are covered. We hope that this review will provide insights into the rational design of N donor-protected metal nanoclusters in terms of structural and functional modulation.
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Liu CY, Yuan SF, Wang S, Guan ZJ, Jiang DE, Wang QM. Structural transformation and catalytic hydrogenation activity of amidinate-protected copper hydride clusters. Nat Commun 2022; 13:2082. [PMID: 35440582 PMCID: PMC9018778 DOI: 10.1038/s41467-022-29819-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/22/2022] [Indexed: 02/06/2023] Open
Abstract
Copper hydrides are important hydrogenation catalysts, but their poor stability hinders the practical applications. Ligand engineering is an effective strategy to tackle this issue. An amidinate ligand, N,N'-Di(5-trifluoromethyl-2-pyridyl)formamidinate (Tf-dpf) with four N-donors has been applied as a protecting agent in the synthesis of stable copper hydride clusters: Cu11H3(Tf-dpf)6(OAc)2 (Cu11) with three interfacial μ5-H and [Cu12H3(Tf-dpf)6(OAc)2]·OAc (Cu12) with three interstitial μ6-H. A solvent-triggered reversible interconversion between Cu11 and Cu12 has been observed thanks to the flexibility of Tf-dpf. Cu11 shows high activity in the reduction of 4-nitrophenol to 4-aminophenol, while Cu12 displays very low activity. Deuteration experiments prove that the type of hydride is the key in dictating the catalytic activity, for the interfacial μ5-H species in Cu11 are involved in the catalytic cycle whereas the interstitial μ6-H species in Cu12 are not. This work highlights the role of hydrides with regard to catalytic hydrogenation activity.
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Li JJ, Liu CY, Guan ZJ, Lei Z, Wang QM. Anion‐Directed Regulation of Structures and Luminescence of Heterometallic Clusters. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202201549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Guan ZJ, He RL, Yuan SF, Li JJ, Hu F, Liu CY, Wang QM. Ligand Engineering toward the Trade-Off between Stability and Activity in Cluster Catalysis. Angew Chem Int Ed Engl 2022; 61:e202116965. [PMID: 35014157 DOI: 10.1002/anie.202116965] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Indexed: 01/08/2023]
Abstract
We report the structures, stability and catalysis properties of two Ag21 nanoclusters, namely [Ag21 (H2 BTCA)3 (O2 PPh2 )6 ]SbF6 (1) and [Ag21 (C≡CC6 H3 -3,5-R2 )6 (O2 PPh2 )10 ]SbF6 (2) (H4 BTCA=p-tert-butylthiacalix[4]arene, R=OMe). Both Ag21 structures possess an identical icosahedral kernel that is surrounded by eight peripheral Ag atoms. Single-crystal structural analysis and ESI-MS revealed that 1 is an 8-electron cluster and 2 has four free electrons. Theoretical results show that the P-symmetry orbitals are found as HOMO-1 and HOMO states in 1, and the frontier unoccupied molecular orbitals (LUMO, LUMO+1 and LUMO+2) show D-character, indicating 1 is a superatomic cluster with an electronically closed shell 1S2 1P6 , while 2 has an incomplete shell configuration 1S2 1P2 . These two Ag21 clusters show superior stability under ambient conditions, and 1 is robust even at 90 °C in toluene and under oxidative conditions (30 % H2 O2 ). Significantly, 2 exhibits much higher activity than 1 as catalyst in the reduction of 4-nitrophenol. This work demonstrates that ligands can influence the electronic structures of silver clusters, and further affect their stability and catalytic performance.
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Li JJ, Liu Z, Guan ZJ, Han XS, Shi WQ, Wang QM. A 59-Electron Non-Magic-Number Gold Nanocluster Au 99(C≡CR) 40 Showing Unexpectedly High Stability. J Am Chem Soc 2022; 144:690-694. [PMID: 34994558 DOI: 10.1021/jacs.1c11643] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An atomically resolved gold nanocluster Au99(C≡CC6H3-2,4-F2)40 (Au99) with an unusual 59 valence electrons has been synthesized. Single-crystal X-ray diffraction reveals that its Au79 kernel is a Au49 Marks decahedron capped by two Au15 units. The surface structure of Au99 consists of 20 linear Au(C≡CR)2 staples. Intercluster interactions are observed between these D5 symmetric clusters. The existence of an unpaired electron is verified by magnetic measurement. Interestingly, this open-shell gold cluster Au99 stays intact in toluene solution at 80 °C for more than a week, and it has good charging-discharging capability under electrochemical conditions. The compact ligand shell protection around the symmetric core accounts for the high stability. This work suggests that geometric factors may play a crucial role in determining the stability of a metal nanocluster, even though the cluster has an open-shell electronic structure.
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Kang SY, Nan ZA, Wang QM. Superatomic Orbital Splitting in Coinage Metal Nanoclusters. J Phys Chem Lett 2022; 13:291-295. [PMID: 34978829 DOI: 10.1021/acs.jpclett.1c03563] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The superatomic orbital splitting (SOS) method is developed to understand the electronic structures of coinage metal nanoclusters, in which delocalized electron counts are not magic numbers. Because the symmetry of a metal core can significantly affect the electronic structure of a nanocluster, this method takes the shape of the core into account in determining the order of group orbital levels. By taking nanoclusters as superatoms, a highly positively charged core is established by removing the ligands and staples. The superatomic orbitals split into group orbitals at different energy levels because of the nonspherical shape of the cluster core. Therefore, the electron configuration of the nonmagic-number nanocluster can be qualitatively analyzed without quantum chemical calculations, which is very important for understanding the stability of the cluster.
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Shi WQ, Guan ZJ, Li JJ, Han XS, Wang QM. Site-Specified Doping of Silver Atoms into Au25 Nanocluster as Directed by Ligand Binding Preference. Chem Sci 2022; 13:5148-5154. [PMID: 35655555 PMCID: PMC9093122 DOI: 10.1039/d2sc00012a] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 03/12/2022] [Indexed: 11/21/2022] Open
Abstract
For the first time site-specific doping of silver into a spherical Au25 nanocluster has been achieved in [Au19Ag6(MeOPhS)17(PPh3)6] (BF4)2 (Au19Ag6) through a dual-ligand coordination strategy. Single crystal X-ray structural analysis shows that the cluster has a distorted centered icosahedral Au@Au6Ag6 core of D3 symmetry, in contrast to the Ih Au@Au12 kernel in the well-known [Au25(SR)18]− (R = CH2CH2Ph). An interesting feature is the coexistence of [Au2(SPhOMe)3] dimeric staples and [P–Au–SPhOMe] semi-staples in the title cluster, due to the incorporation of PPh3. The observation of only one double-charged peak in ESI-TOF-MS confirms the ordered doping of silver atoms. Au19Ag6 is a 6e system showing a distinct absorption spectrum from [Au25(SR)18]−, that is, the HOMO–LUMO transition of Au19Ag6 is optically forbidden due to the P character of the superatomic frontier orbitals. For the first time site-specific doping of silver into a spherical Au25 nanocluster has been achieved in [Au19Ag6(MeOPhS)17(PPh3)6] (BF4)2. It is a 6e system showing quite a different absorption spectrum from [Au25(SR)18]−.![]()
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Zhu JY, Mei ZB, Zhang ZJ, Yang W, Zhao WW, Xu J, Zou QQ, Wang QM. [Clinical efficacy of the modified separation of external anal sphincter for the treatment of high horseshoe anal fistula]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2021; 24:1111-1115. [PMID: 34923798 DOI: 10.3760/cma.j.cn441530-20201031-00581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
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22
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Wang S, Li SM, Wu X, Zhu H, Wang QM. [Crizotinib treatment for a lung adenocarcinoma patient with anaplastic lymphoma kinase gene rearrangement and disseminated intravascular coagulation]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2021; 43:1195-1196. [PMID: 34794223 DOI: 10.3760/cma.j.cn112152-20200611-00549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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23
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Hu F, Guan ZJ, Yang G, Wang JQ, Li JJ, Yuan SF, Liang GJ, Wang QM. Molecular Gold Nanocluster Au 156 Showing Metallic Electron Dynamics. J Am Chem Soc 2021; 143:17059-17067. [PMID: 34609874 DOI: 10.1021/jacs.1c06716] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The boundary between molecular and metallic gold nanoclusters is of special interest. The difficulty in obtaining atomically precise nanoclusters larger than 2 nm limits the determination of such a boundary. The synthesis and total structural determination of the largest all-alkynyl-protected gold nanocluster (Ph4P)6[Au156(C≡CR)60] (R = 4-CF3C6H4-) (Au156) are reported. It presents an ideal platform for studying the relationship between the structure and the metallic nature. Au156 has a rod shape with the length and width of the kernel being 2.38 and 2.04 nm, respectively. The cluster contains a concentric Au126 core structure (Au46@Au50@Au30) protected by 30 linear RC≡C-Au-C≡CR staple motifs. It is interesting that Au156 displays multiple excitonic peaks in the steady-state absorption spectrum (molecular) and pump-power-dependent excited-state dynamics as revealed in the transient absorption spectrum (metallic), which indicates that Au156 is a critical crossover cluster for the transition from molecular to metallic state. Au156 is the smallest-sized gold nanocluster showing metal-like electron dynamics, and it is recognized that the cluster shape is one of the important factors determining the molecular or metallic nature of a gold nanocluster.
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Wan XK, Wang JQ, Wang QM. Ligand-Protected Au 55 with a Novel Structure and Remarkable CO 2 Electroreduction Performance. Angew Chem Int Ed Engl 2021; 60:20748-20753. [PMID: 34288322 DOI: 10.1002/anie.202108207] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Indexed: 01/22/2023]
Abstract
A Au55 nanocluster with the composition of [Au55 (p-MBT)24 (Ph3 P)6 ](SbF6 )3 (p-MBT=4-methylbenzenethiolate) is synthesized via direct reduction of gold-phosphine and gold-thiolate precursors. Single-crystal X-ray diffraction reveals that this Au55 nanocluster features a face-centered cubic (fcc) Au55 kernel, different from the well-known two-shell cuboctahedral arrangement in Au55 (Ph3 P)12 Cl6 . The Au55 cluster shows a wide optical absorption band with optical energy gap (Eg =1.28 eV). It is found that the exclusion of chloride is crucial for the formation of the title cluster, otherwise rod-like [Au25 (SR)5 (PPh3 )10 Cl2 ]2+ is obtained. The strategy to run synthetic reaction in the absence of halide leads to new members of phosphine/thiolate co-protected metal nanoclusters. The Au55 nanocluster exhibits high catalytic activity and selectivity for electrochemical reduction of CO2 to CO; the Faradaic efficiency (FE) reaches 94.1 % at -0.6 V vs. reversible hydrogen electrode (RHE).
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25
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Yuan SF, Xu CQ, Liu WD, Zhang JX, Li J, Wang QM. Rod-Shaped Silver Supercluster Unveiling Strong Electron Coupling between Substituent Icosahedral Units. J Am Chem Soc 2021; 143:12261-12267. [PMID: 34324334 DOI: 10.1021/jacs.1c05283] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The first linear silver supercluster based on icosahedral Ag13 units has been constructed via bridging of dpa ligands: Ag61(dpa)27(SbF6)4 (Hdpa = dipyridylamine) (Ag61). Single-crystal X-ray diffraction reveals that this rod-shaped cluster consists of four vertex-sharing Ag13 icosahedra in a linear arrangement. This Ag61 cluster represents the longest one-dimensional metal nanocluster with a resolved structure. Unprecedented electron coupling develops between their constituent Ag13 units. Theoretical studies disclose that the stabilities of the two superclusters are dictated by a strong interaction between the Ag13 units as well as the ligand effect of the dpa-Ag motifs. The quantum size effect accounts for the significant enhancement of the metal-related absorptions and the red shift at the near-infrared region as the length of the cluster increases. This work sheds light on the evolution of one-dimensional materials and an understanding of the electronic communication between the constituent clusters.
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