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Diselenophosphate‐Induced Conversion of an Achiral [Cu20H11{S2P(OiPr)2}9] into a Chiral [Cu20H11{Se2P(OiPr)2}9] Polyhydrido Nanocluster
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Dr. Rajendra S. Dhayal Jian‐Hong Liao Dr. Xiaoping Wang Dr. Yu‐Chiao Liu Dr. Ming‐His Chiang Dr. Samia Kahlal Prof. Jean‐Yves Saillard Prof. C. W. Liu 《Angewandte Chemie (International ed. in English)》2015,54(46):13604-13608
A polyhydrido copper nanocluster, [Cu20H11{Se2P(OiPr)2}9] ( 2H ), which exhibits an intrinsically chiral inorganic core of C3 symmetry, was synthesized from achiral [Cu20H11{S2P(OiPr)2}9] ( 1H ) of C3h symmetry by a ligand‐exchange method. The structure has a distorted cuboctahedral Cu13 core, two triangular faces of which are capped along the C3 axis, one by a Cu6 cupola and the other by a single Cu atom. The Cu20 framework is further stabilized by 9 diselenophosphate and 11 hydride ligands. The number of hydride, phosphorus, and selenium resonances and their splitting patterns in multinuclear NMR spectra of 2H indicate that the chiral Cu20H11 core retains its C3 symmetry in solution. The 11 hydride ligands were located by neutron diffraction experiments and shown to be capping μ3‐H and interstitial μ5‐H ligands (in square‐pyramidal and trigonal‐bipyramidal cavities), as supported by DFT calculations on [Cu20H11(Se2PH2)9] ( 2H′ ) as a simplified model. 相似文献
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Maksim Kulichenko Nikita Fedik Prof. Dr. Alexander Boldyrev Prof. Dr. Alvaro Muñoz-Castro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(10):2263-2268
Structural characterization of the discrete [Sn@Cu12@Sn20]12− cluster exposed a fascinating architecture composed of three concentric structural layers in which an endohedral Sn atom is enclosed in a Cu12 icosahedron, which in turn is embedded in an Sn20 dodecahedron. Herein, the possibility of sustaining aromatic behavior for this prototypical multilayered species was evaluated, in order to extend this concept to more complex clusters on the basis of magnetic response and bonding analysis by the AdNDP approach. This revealed characteristic features of spherical aromatics, given by the ability to sustain the shielding cone property, similar to archetypal aromatics. The favorable bonding pattern in the [Sn@Cu12@Sn20]12− cluster fulfills the 2(N+1)2 Hirsch rule for aromaticity; thus, the cluster could be regarded as a first member of aromatic multilayered structures. The set of four 13c–2e aromatic bonds that was identified in the internal SnCu12 structure results in spherical aromatic character of this multilayered cluster. This insight builds a bridge between the traditional concept of Hückel's aromaticity and the aromaticity of complex and stable 3D systems that may be explored on the basis of magnetic response and bonding analysis. It also may open a way to novel findings in bottled clusters displaying aromatic behavior in multilayer structures, which are of great interest for inorganic nano- and material sciences due to their unprecedented stability. 相似文献
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Dr. Subrat Kumar Barik Shou-Chih Huo Chun-Yen Wu Tzu-Hao Chiu Jian-Hong Liao Dr. Xiaoping Wang Dr. Samia Kahlal Prof. Jean-Yves Saillard Prof. C. W. Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(46):10471-10479
Although atomically precise polyhydrido copper nanoclusters are of prime interest for a variety of applications, they have so far remained scarce. Herein, this work describes the synthesis of a dithiophosphate-protected copper(I) hydride-rich nanocluster (NC), [Cu30H18{S2P(OnPr)2}12] ( 1H ), fully characterized by various spectroscopic methods and single-crystal X-ray diffraction. The X-ray structure of 1H reveals an unprecedented central Cu12 hollow icosahedron. Six faces of this icosahedron are capped by Cu3 triangles, the whole Cu30 core being wrapped by twelve dithiophosphate ligands and the whole cluster has ideal S6 symmetry. The locations of the 18 hydrides in 1H were ascertained by a single-crystal neutron diffraction study. They are composed of three types: capping μ3-H, interstitial μ4-H (seesaw) and μ5-H ligands (square pyramidal), in good agreement with the DFT simulations. The numbers of hydrides and ligand resonances in the 1H NMR spectrum of 1H are in line with their coordination environment in the solid state, retaining the S6 symmetry in solution. Furthermore, two new Se-protected polyhydrido copper nanoclusters, [Cu30H18{Se2P(OR)2}12] ( 2H : R=iPr 3H : R=iBu) were synthesized from their sulfur relative 1H via ligand displacement reaction and their X-ray structures feature the exceptional case where both the NC shape and size are fully conserved during the course of ligand exchange. DFT and TD-DFT calculations allow understanding the bonding and optical properties of clusters 1H – 3H . In addition, the reaction of 1H with [Pd(PPh3)2Cl2] in the presence of terminal alkynes led to the formation of new bimetallic Cu−Pd alloy clusters [PdCu14H2{S2P(OnPr)2}6(C≡CR)6] ( 4 : R=Ph; 5 : R = C6H4F). 相似文献
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Dr. Rajendra S. Dhayal Jian‐Hong Liao Dr. Yu‐Chiao Liu Dr. Ming‐His Chiang Dr. Samia Kahlal Prof. Jean‐Yves Saillard Prof. C. W. Liu 《Angewandte Chemie (International ed. in English)》2015,54(12):3702-3706
A novel discrete [Ag21{S2P(OiPr)2}12](PF6) nanocluster has been synthesized and characterized by single‐crystal X‐ray diffraction and also NMR spectroscopy (1H, 31P), ESI mass spectrometry, and other analytic techniques (XPS, EDS, UV/Vis spectroscopy). The Ag21 skeleton has an unprecedented silver‐centered icosahedron that is capped by eight additional metal atoms. The whole framework is protected by twelve dithiophosphate ligands. According to the spherical Jellium model, the stability of monocationic nanocluster can be described by an 8‐electron superatom with 1S2 1P6 configuration, as confirmed by DFT calculations. 相似文献
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Synthesis and Characterization of a Cu14 Hydride Cluster Supported by Neutral Donor Ligands
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Thuy‐Ai D. Nguyen Bryan R. Goldsmith Homaira T. Zaman Dr. Guang Wu Prof. Dr. Baron Peters Prof. Dr. Trevor W. Hayton 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5341-5344
The copper hydride clusters [Cu14H12(phen)6(PPh3)4][X]2 (X=Cl or OTf; OTf=trifluoromethanesulfonate, phen=1,10‐phenanthroline) are obtained in good yields by the reaction of [(Ph3P)CuH]6 with phen, in the presence of a halide or pseudohalide source. The complex [Cu14H12(phen)6(PPh3)4][Cl]2 reacts with CO2 in CH2Cl2, in the presence of excess Ph3P, to form the formate complex [(Ph3P)2Cu(κ2‐O2CH)], along with [(phen)(Ph3P)CuCl]. 相似文献
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[FeFe] Hydrogenase: Protonation of {2Fe3S} Systems and Formation of Super‐reduced Hydride States
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Aušra Jablonskytė Dr. Joseph A. Wright Dr. Shirley A. Fairhurst Dr. Lee R. Webster Prof. Christopher J. Pickett 《Angewandte Chemie (International ed. in English)》2014,53(38):10143-10146
The synthesis and crystallographic characterization of a complex possessing a well‐defined {2Fe3S(μ‐H)} core gives access to a paramagnetic bridging hydride with retention of the core geometry. Chemistry of this 35‐electron species within the confines of a thin‐layer FTIR spectro‐electrochemistry cell provides evidence for a unprecedented super‐reduced FeI(μ‐H)FeI intermediate. 相似文献
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Muhammad O. Ali John C. Lasseter Dr. Remigiusz Żurawiński Dr. Anna Pietrzak Dr. Jacek Pecyna Dr. Jakub Wojciechowski Prof. Andrienne C. Friedli Dr. Damian Pociecha Prof. Piotr Kaszyński 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(10):2616-2630
Two series of 1,12-bis-zwitterionic derivatives of the [closo-B12H12]2− anion ( B ), containing either two 4-alkoxypyridinium groups ( 1B[n]-p ) or one 4-alkoxypyridinium and one 4-pentylthianium groups ( 2B[n]-p ), were prepared and their structural (XRD, DFT), thermal, and photophysical properties were compared with those of the analogous derivatives of the [closo-B10H10]2− anion ( 1A[n]-p and 2A[n]-p ). Some 1,7-derivatives of B were isolated and investigated. Both series 1[n] and 2[n] exhibit nematic and crystalline polymorphism; the 12-vertex derivatives ( B ) have higher transition temperatures than those of the 10-vertex analogues ( A ). All compounds fluoresce with quantum yields higher for 1B (ΦF=0.37 for 1B[7]-p and ΦF=0.27 for 2B[7]-p ) than those for the 10-vertex analogues (ΦF=0.04 for 2A[5]-p ). DFT calculations demonstrate an order of magnitude lower first hyperpolarizability, β(−ω,ω,0), for 2B[7]-p than that for the 10-vertex analogue 2A[7]-p (1.7×10−30 vs. 18.9×10−30 esu at ω=0). 相似文献
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Dr. Siddhartha De Dr. Alexandrine Flambard Dr. Delphine Garnier Patrick Herson Dr. Frank H. Köhler Dr. Abhishake Mondal Dr. Karine Costuas Dr. Béatrice Gillon Prof. Rodrigue Lescouëzec Dr. Boris Le Guennic Dr. Frédéric Gendron 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(52):12120-12136
The local magnetic structure in the [FeIII(Tp)(CN)3]− building block was investigated by combining paramagnetic Nuclear Magnetic Resonance (pNMR) spectroscopy and polarized neutron diffraction (PND) with first-principle calculations. The use of the pNMR and PND experimental techniques revealed the extension of spin-density from the metal to the ligands, as well as the different spin mechanisms that take place in the cyanido ligands: Spin-polarization on the carbon atoms and spin-delocalization on the nitrogen atoms. The results of our combined density functional theory (DFT) and multireference calculations were found in good agreement with the PND results and the experimental NMR chemical shifts. Moreover, the ab-initio calculations allowed us to connect the experimental spin-density map characterized by PND and the suggested distribution of the spin-density on the ligands observed by NMR spectroscopy. Interestingly, significant differences were observed between the pseudo-contact contributions of the chemical shifts obtained by theoretical calculations and the values derived from NMR spectroscopy using a simple point-dipole model. These discrepancies underline the limitation of the point-dipole model and the need for more elaborate approaches to break down the experimental pNMR chemical shifts into contact and pseudo-contact contributions. 相似文献
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Dr. Ulrike Helmstedt Dr. Eric Clot 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(36):11449-11458
The catalytic cycle for the Murai reaction at room temperature between ethylene and acetophenone catalyzed by [Ru(H)2(H2)2(PMe3)2] has been studied computationally at the B3PW91 level. The active species is the ruthenium dihydride complex [Ru(H)2(PMe3)2]. Coordination of the ketone group to Ru induces very easy C H bond cleavage. Coordination of ethylene after ketone de-coordination, followed by ethylene insertion into a Ru H bond, creates the Ru ethyl bond. Isomerization of the complex to a RuIV intermediate creates the geometry adapted to C C bond formation. Re-coordination of the ketone before the C C coupling lowers the energy of the corresponding TS. The highest point on the potential energy surface (PES) is the TS for the isomerization to the RuIV intermediate, which prepares the catalyst geometry for the C C coupling step. Inclusion of dispersion corrections significantly lowers the height of the overall activation barrier. The actual bond cleavage and bond forming processes are associated to low activation barriers because of the presence of hydrogen atoms around the Ru center. They act as redox buffers through formation and breaking of H H bonds in the coordination sphere. This flexibility allows optimal repartition of the various ligands according to the change in stereoelectronic demands along the catalytic cycle. 相似文献
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Reinoso S Vitoria P San Felices L Lezama L Gutiérrez-Zorrilla JM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(5):1538-1548
The reaction of a monosubstituted Keggin polyoxometalate (POM) generated in situ with copper-phenanthroline complexes in excess ammonium or rubidium acetate led to the formation of the hybrid metal organic-inorganic compounds A7[Cu2(ac)2(phen)2(H2O)2][Cu3(ac)3(phen)3(H2O)3][Si2W22Cu2O78(H2O)].approximately 18 H2O (A=NH4+ (1), Rb+ (2); ac=acetate; phen=1,10-phenanthroline). These compounds are constructed from inorganic and metalorganic interpenetrated sublattices containing the novel bimolecular Keggin POM, [Si2W22Cu2O78(H2O)]12-, and Cu-ac-phen complexes, [Cu(ac)(phen)(H2O)]n n+ (n=2, 3). The packing of compound 1 can be viewed as a stacking of open-framework layers parallel to the xy plane built of hydrogen-bonded POMs, and zigzag columns of pi-stacked Cu-ac-phen complex cations running along the [111] direction. Magnetic and EPR results are discussed with respect to the crystal structure of the compounds. DFT calculations on [Cu(ac)(phen)(H2O)]n n+ cationic complexes have been performed, to check the influence of packing in the complex geometry and determine the magnetic exchange pathways. 相似文献