Interaction of [Mo6Cl14]2− with H2Se: Selective Preparation of [Mo6SeCl13]3−

Reaction of [Mo₆(μ₃-Cl)₈Cl₆]²⁻ with H₂Se, generated in situ from ZnSe and 4 M HCl under hydrothermal conditions lead to the substitution of one or two bridging chlorides, depending on the reagents ratio. With the Mo₆/ZnSe 1:3 molar ratio [Mo₆(μ₃-SeCl₇)Cl₆]³⁻ forms selectively in high yield. Further substitution is more hindered, and even at 1:20 cluster-to-selenide molar ratio a mixture of [Mo₆(μ₃-SeCl₇)Cl₆]³⁻ and [Mo₆(μ₃-Se₂Cl₆)Cl₆]⁴⁻ is formed. The products were characterized by X-ray, Raman spectra and electrospray ionization mass spectrometry.     

Single-Metal-Encapsulated Double-Cage [Pt@Sn17]4−: An Exception from Group 14 Endohedral Clusters

Group 14 endohedral clusters containing a metal center inside usually possess a single cage topological structure, but here an unexpected single-metal-filled double-cage cluster, [Pt@Sn₁₇]⁴⁻ ( 1 a ) is reported. It can be seen as a combination of the more extended Pt-filled [Pt@Sn₉] cage and hollow [Sn₉] cage sharing a central Sn atom, which is offset from the central position. This double-cage species represents the largest group 14 intermetalloid cluster encapsulating a single transition metal atom. DFT calculations show that the capsule-like architecture of [Sn₁₇]⁴⁻, similar to that found in [Pt₂@Sn₁₇]⁴⁻, is unstable if filled with a single Pt atom and collapses to the title cluster 1 a upon geometry optimization. Deviation of the central Sn atom occurs due to the vibronic coupling as a consequence of pseudo-Jahn-Teller distortion leading to the bent C_s-symmetrical structure, in contrast to the more symmetrical D_2d cage previously reported in [Ni₂@Sn₁₇]⁴⁻.     

Diversity of Functionalized Germanium Zintl Clusters: Syntheses and Theoretical Studies of [Ge9PdPPh3]3− and [Ni@(Ge9PdPPh3)]2−

Abstract  A new Zintl cluster [Ge₉PdPPh₃]³⁻ has been isolated as (2,2,2-crypt)K⁺ salt through the reaction of K₄Ge₉ and Pd[PPh₃]₄ in ethylenediamine solutions and characterized via single-crystal X-ray crystallography. The as-prepared bimetallic [Ge₉PdPPh₃]³⁻ cluster could successfully trap a nickel atom to form a trimetallic cluster [Ni@(Ge₉PdPPh₃)]²⁻. The coordination of Ge₉ ⁴⁻ by PdPPh₃ induces a one-electron oxidation and encapsulation of the Ni atom into the Ge₉ ³⁻ cage leads to a further one-electron oxidation and a geometry transformation from C_4v (nido) to C_3v (closo). Graphical Abstract   Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

σ-Aromaticity-Induced Stabilization of Heterometallic Supertetrahedral Clusters [Zn6Ge16]4− and [Cd6Ge16]4−

In this work, the largest heterometallic supertetrahedral clusters, [Zn₆Ge₁₆]⁴⁻ and [Cd₆Ge₁₆]⁴⁻, were directly self-assembled through highly-charged [Ge₄]⁴⁻ units and transition metal cations, in which 3-center–2-electron σ bonding in Ge₂Zn or Ge₂Cd triangles plays a vital role in the stabilization of the whole structure. The cluster structures have an open framework with a large central cavity of diameter 4.6 Å for Zn and 5.0 Å for Cd, respectively. Time-dependent HRESI-MS spectra show that the larger clusters grow from smaller components with a single [Ge₄]⁴⁻ and ZnMes₂ units. Calculations performed at the DFT level indicate a very large HOMO–LUMO energy gap in [M₆Ge₁₆]⁴⁻ (2.22 eV), suggesting high kinetic stability that may offer opportunities in materials science. These observations offer a new strategy for the assembly of heterometallic clusters with high symmetry.     

Synthesis and structure of antimony iodide complexes: [Ph3MeP] + 2 [SbI5]2−, [Ph3MeP] + 3 [Sb3I12]3−·Me2C=O, [Ph3MeP] + 3 [Sb3I12]3−, and [Ph3MeP] + 3 [Sb2I9]3−

Complexes with antimony-containing anions, [Ph₃MeP] ₊ ² [SbI₅]^2? (I), [Ph₃MeP] ₊ ² [Sb₃I₁₂]^3? (II), [Ph₃MeP] ₊ ³ [Sb₃I₁₂]^3? · Me₂C=O (III), and [Ph₃MeP] ₊ ³ [Sb₂I₉]^3? (IV), were synthesized by reacting triphenylmethylphosphonium iodide with antimony iodide. The central atom in the cations of the complexes has a distorted tetrahedral coordination. In the trinuclear anions of complexes II and III, each of the terminal SbI₃ groups is bound to the central Sb atom through two μ₂- and one μ₃ iodine bridges (SbSbSb angles are 103.0° and 102.2°, respectively). In the binuclear anion of complex IV, antimony atoms are linked with each other via three bridging iodine atoms.     

Insights into the Electrochemical Polymerization of [Mo3S13]2− Generating Amorphous Molybdenum Sulfide

Amorphous molybdenum sulfide is an attractive electrode material for Li/Mg batteries and an efficient Pt-free catalyst for the hydrogen evolution reaction in water. By using the electrochemical quartz crystal microbalance (EQCM) analysis, new insights were gained into the electrochemical polymerization of the [Mo₃S₁₃]²⁻ cluster, which generates amorphous molybdenum sulfide thin films. In this work, it is shown that, at the anodic potential, a two-electron oxidative elimination of the terminal disulfide ligand within the [Mo₃S₁₃]²⁻ cluster induces the polymerization. A reductive elimination of the terminal disulfide ligand also occurs at the cathodic potential, inducing the polymerization. However, in sharp contrast to the anodic polymerization, according to which the film growth is rapid, the cathodic polymerization competes with the electrochemical reductive corrosion of the readily grown film, therefore occurring at a significant lower growth rate.     

Stabilization of Guanidinate Anions [CN3]5− in Calcite-Type SbCN3

The stabilization of nitrogen-rich phases presents a significant chemical challenge due to the inherent stability of the dinitrogen molecule. This stabilization can be achieved by utilizing strong covalent bonds in complex anions with carbon, such as cyanide CN⁻ and NCN²⁻ carbodiimide, while more nitrogen-rich carbonitrides are hitherto unknown. Following a rational chemical design approach, we synthesized antimony guanidinate SbCN₃ at pressures of 32–38 GPa using various synthetic routes in laser-heated diamond anvil cells. SbCN₃, which is isostructural to calcite CaCO₃, can be recovered under ambient conditions. Its structure contains the previously elusive guanidinate anion [CN₃]⁵⁻, marking a fundamental milestone in carbonitride chemistry. The crystal structure of SbCN₃ was solved and refined from synchrotron single-crystal X-ray diffraction data and was fully corroborated by theoretical calculations, which also predict that SbCN₃ has a direct band gap with the value of 2.20 eV. This study opens a straightforward route to the entire new family of inorganic nitridocarbonates.     

meso Myths: What Drives Assembly of Helical versus meso-[M2L3] Clusters?

Both a triple helix as well as a meso complex are formed by the Ga^III and Al^III complexes with a bis-bidentate bis-hydroxypyridinone ligand H₂L. The two forms are in equilibrium in solution, though formation of the helical structure in the presence of water, which as guest molecule finds sufficient space in the cavity of the helix, is favored (the structure of the helical H₂O⊂[Al₂L₃] complex is shown).     

The Rb7Bi3−3xSb3xCl16 Family: A Fully Inorganic Solid Solution with Room-Temperature Luminescent Members

Low-dimensional ns²-metal halide compounds have received immense attention for applications in solid-state lighting, optical thermometry and thermography, and scintillation. However, these are based primarily on the combination of organic cations with toxic Pb²⁺ or unstable Sn²⁺, and a stable inorganic luminescent material has yet to be found. Here, the zero-dimensional Rb₇Sb₃Cl₁₆ phase, comprised of isolated [SbCl₆]³⁻ octahedra and edge-sharing [Sb₂Cl₁₀]⁴⁻ dimers, shows room-temperature photoluminescence (RT PL) centered at 560 nm with a quantum yield of 3.8±0.2 % at 296 K (99.4 % at 77 K). The temperature-dependent PL lifetime rivals that of previous low-dimensional materials with a specific temperature sensitivity above 0.06 K⁻¹ at RT, making it an excellent thermometric material. Utilizing both DFT and chemical substitution with Bi³⁺ in the Rb₇Bi_3−3xSb_3xCl₁₆ (x≤1) family, we present the edge-shared [Sb₂Cl₁₀]⁴⁻ dimer as a design principle for Sb-based luminescent materials.     

Synthesis of New Polycyclic Compounds Containing Thieno[2′,3′:5,6]pyrimido[2,1-a]isoindole Fragment

Russian Journal of General Chemistry - The reaction of partially saturated derivatives of 3-aminothieno[2,3-b]pyridine-2-carboxamide with phthalic anhydride in acetic acid or DMF on heating leads...     

New convenient synthesis of substituted 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-b]pyridines and 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-d]pyrimidines

1,4-Dihydro-3-cyano-2-pyridinethiolates react with 2-bromo-l-(4-bromophenyl)ethylidenemalononitrile or N-cyanochloracetanudine to give 6, 9-dihydropyrido[3, 2': 4, 5]thieno[3. 2-b]pyridines or 6, 9-dihydropyrido-[3.2:4.5Jthieno(3,2-d]pyrimidines, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 553–556, April, 1996.     

New Approach to Synthesis of Tetrahydroisoquino[2,1-c] [1,3]benzodiazepine

A concise and efficient synthesis of the new compounds tetrahydroisoquino [2,1-c] [1,3]benzodiazepine 5 and 7 is reported.     

Coexistence of Two Different Distorted Octahedral [MnF6]3− Sites in K3[MnF6]: Manifestation in Spectroscopy and Magnetism

As a consequence of the static Jahn-Teller effect of the ⁵E ground state of Mn^III in cubic structures with octahedral parent geometries, their octahedral coordination spheres become distorted. In the case of six fluorido ligands, [MnF₆]³⁻ anions with two longer and four shorter Mn−F bonds making elongated octahedra are usually observed. Herein, we report the synthesis of the compound K₃[MnF₆] through a high-temperature approach and its crystallization by a high-pressure/high-temperature route. The main structural motifs are two quasi-isolated, octahedron-like [MnF₆]³⁻ anions of quite different nature compared to that met in ideal octahedral Mn^III Jahn-Teller systems. Owing to the internal electric field of C_i symmetry dominated by the next-neighbour K⁺ ions acting on the Mn^III sites, both sites, the pseudo-rhombic (site 1) and the pseudo-tetragonally elongated (site 2) [MnF₆]³⁻ anions are present in K₃[MnF₆]. The compound was characterized by single-crystal and powder X-ray diffraction, and magnetometry as well as by FTIR, Raman, and ligand field spectroscopy. A theoretical interpretation of the electronic structure and molecular geometry of the two Mn sites in the lattice is given by using a vibronic coupling model with parameters adjusted from multireference ab-initio cluster calculations.     

Synthesis of Calix[4]pyrroles: A Class of New Molecular Receptor

RecentlySesslerandco-workersdiscoveredthatthemeso-octaalkylporphyrinogensshowedinterestinganionandneutralsubstratebindingpropertiesandmightserveasaclassofneweasy-to-makemolecularreceptorintheareaofsupramolecularchemistry'.However,themeso-octaalkylpor...     

A New Short Synthesis of 3, 3′-Methylene Bis[Coumarins] and 3,3-Methylene Bis[2-Diethylaminoquinolines]

Hitherto unknown six symmetrically and unsymmetrically substituted methylene bis(coumarins) and two methylene bis(quinolines) are synthesised by using 1:2 complex of N, N, N', N'-tetraethyl glutaramide with POCl₃ and its condensation with substituted salicyl-aldehydes and o-formyl acetanilides.     

New Approach to Synthesis of Tetrahydroisoquino[2,l-c] [1,3]-benzodiazepine

A concise and efficient synthesis of the new compounds tetrahydroisoquino [2,1-c] [1,3] benzodiazepine 5 and 7 is reported.     

Substituent Effect to Fine-Tune Energy Levels of Atom-Precise [MoOS3]2− Modified Copper(I) Thiolate Clusters Boosting Recyclable Photocatalysis

The propulsion of photocatalytic hydrogen (H₂) production is limited by the rational design and regulation of catalysts with precise structures and excellent activities. In this work, the [MoOS₃]²⁻ unit is introduced into the Cu^I clusters to form a series of atomically-precise Mo^VI−Cu^I bimetallic clusters of [Cu₆(MoOS₃)₂(C₆H₅(CH₂)S)₂(P(C₆H₄−R)₃)₄] ⋅ xCH₃CN (R=H, CH₃, or F), which show high photocatalytic H₂ evolution activities and excellent stability. By electron push-pull effects of the surface ligand, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of these Mo^VI−Cu^I clusters can be finely tuned, promoting the resultant visible-light-driven H₂ evolution performance. Furthermore, Mo^VI−Cu^I clusters loaded onto the surface of magnetic Fe₃O₄ carriers significantly reduced the loss of catalysts in the collection process, efficiently addressing the recycling issues of such small cluster-based catalyst. This work not only highlights a competitively universal approach on the design of high-efficiency cluster photocatalysts for energy conversion, but also makes it feasible to manipulate the catalytic performance of clusters through a rational substituent strategy.     

Synthesis of New Pyrido[4″,3″:4″,5″]thieno[2″,3″:4,5]pyrimido[2,1-b][1,3,4]thiadiazine Derivatives

Ethyl 2-methyl-11-oxo-9, 10-dihydro-1 H , 11 H -pyrido[4",3":4',5']thieno[2',3':4,5]pyrimido[2,1-b][1,3,4]thiadiazine-8(7 H )-carboxylate 7 has been synthesised by the reaction of ethyl 3-amino-4-oxo-2-thioxo-1,3,4,5,6,8-hexahydropyrido[4',3':4,5]thieno[2,3-d]pyrimidine-7(2 H )-carboxylate 2 with allylbromide followed by treatment with bromine and subsequent dehydrobromination of the brominated product 5 with ethanolic sodium hydroxide. Its isomeric ethyl 2-methyl-11-oxo-9,10-dihydro-3 H ,11 H -pyrido[4",3Prime;:4',5']thieno[2',3':4,5]pyrimido[2,1-b][1,3,4]thiadiazine-8(7 H )-carboxylate 8 has been obtained by condensation of 2 with chloroacetone followed by cyclization of the intermediate 9 with p -toulenesulfonic acid. The thiadiazino derivatives 11 , 13 , 15 were prepared through the reaction of 2 with the appropriate f -halocarbonyl compounds followed by cyclization reactions of the intermediates 10 , 12 , 14 .