Influence of the synthesis parameters onto nucleation and crystallization of five new tin-sulfur containing compounds

One-Dimensional Selenidostannates Based on an Infrequent Tetrameric Cluster [Sn4Se12] Exhibiting Electro-Catalytic Properties

The discovery of low-cost and efficient electro-catalytic materials for hydrogen evolution reaction (HER) is very desirable in hydrogen energy technology. Here, a new type of one-dimensional (1-D) organic hybrid selenidostannate [Ni(en)₃]_n[Sn₂Se₅]_n (SnSe-1, en = ethylenediamine) with an in situ [Ni(en)₃]²⁺ complex was achieved by the solvothermal reaction of Sn, Se, and NiCl₂·6H₂O in a mixed solvent of en and triethanolamine at 160 °C for 10 days. The crystal structure of SnSe-1 contains a unique 1-D [Sn₂Se₅^2-]_n chain built up from the sharing-edge connection of a hitherto-unknown tetrameric [Sn₄Se₁₂] cluster, which is separated by discrete [Ni(en)₃]²⁺ complexes. SnSe-1 is first combined with Ni nanoparticles supported on conductive porous Ni foam (NF) to constitute a Ni/SnSe-1/NF electrode as the HER electro-catalyst, displaying superior electro-catalytic activity in near-neutral conditions.

Synthesis and Characterization of a Rare Transition-Metal Oxothiostannate and Investigation of Its Photocatalytic Properties

The new transition-metal oxothiostannate [Ni(cyclen)(H₂O)₂]₄[Sn₁₀S₂₀O₄]·∼13H₂O (1) was prepared under hydrothermal conditions using Na₄SnS₄·14H₂O as the precursor in the presence of [Ni(cyclen)(H₂O)₂](ClO₄)₂·H₂O. Compound 1 comprises the [Sn₁₀S₂₀O₄]^8- anion constructed by the T3-type supertetrahedron [Sn₁₀S₂₀] and the [Sn₁₀O₄] anti-T2 cluster. Channels host the H₂O molecules, and the sample can be reversibly dehydrated and rehydrated without significantly affecting the crystallinity of the material. ¹¹⁹Sn NMR spectroscopy of an aqueous solution of Na₄SnS₄·14H₂O evidences that between 25 and 120 °C only [SnS₄]^4- and [Sn₂S₆]^4- anions are present. In further experiments, hints were found that the formation of tin oxosulfide ions depends on the Ni²⁺-centered complexes. Compound 1 exhibits promising photocatalytic properties for the visible-light-driven hydrogen evolution reaction, with 18.7 mmol·g^-1 H₂ being evolved after 3 h.

Alcohol-solvothermal syntheses, crystal structures and photocatalytic properties of tin selenides with polyselenide ligands

New polyselenidostannates with Se₂²⁻ or Se₄²⁻ polyselenide ligands, [TM(en)₃]Sn₃Se₆(Se₂) (1–3), [Ni(en)₃]Sn₃Se_7.5 (4) and [TM(en)₃][Sn(Se₄)₃] (5–8), were prepared by alcohol-solvothermal methods.

Mixing SbIII and GeIV occupancy in the polyoxovanadate {V14E8} archetype

The first mixed germanato-antimonato derivative of the {V14E8O42} (E=semi-metal) cluster archetype has been synthesized under hydrothermal conditions and isolated as {Ni(phen)3}2[α-VIV 14SbIII 5GeIV 3O42(OH)3(H2O)]· ≈16H2O (phen=1,10-phenanthroline). In the cluster anion, seven of the eight hetero-metal positions are occupied by disordered Ge/Sb atoms, while one position is fully occupied by Sb atoms. The [V14Sb5Ge3O42(OH)3(H2O)]6− anions are arranged in pairs with remarkably short inter-cluster Sb···O contacts. Bond valence sum calculation strongly suggests that the Sb···O contact must be taken into account as a weak bond. The magnetic properties are dominated by strong intra-cluster antiferromagnetic exchange interactions, and the cluster anion is magnetically quasi-isolated from the spins of the Ni2+ complex cations.

Flexibility and lability of a phenyl ligand in hetero-organometallic 3d metal-Sn(iv) compounds and their catalytic activity in Baeyer-Villiger oxidation of cyclohexanone

The single compartmental Schiff base N,N'-ethylenebis(salicylaldimine) (H₂L) and [SnPh₂Cl₂] were utilized to synthesize heterobimetallic 3d metal-Sn complexes, the Co^IIISn^IV compound [{SnPhCl₂}(1κO²N²,2κO²-μ-L)(μ-OMe){CoPh}] (1), the Ni^IISn^IV compound [{SnPh₂Cl₂}(1κO²N²,2κO²-μ-L)Ni] (2) and the Cu^IISn^IV compound [{SnPh₂Cl₂}(1κO²N²,2κO²-μ-L)Cu] (3). Attempting to prepare the ethoxido bridged compound analogous to 1 (in ethanol) gives the phenylcobalt(iii) complex [Co(κO²N²)Ph(H₂O)] (1A). Single crystal X-ray structure analyses reveal that 1 is derived from an intermetallic (Sn to Co) phenyl shift and that 1A is a transmetallated product; in compounds 2 and 3, the phenyl groups remain coordinated to Sn^IV but one of the π rings interacts with the 3d-metal. Thus, while systems 1 and 1A show the lability of the phenyl ligand, 2 and 3 reveal its flexible nature. Theoretical DFT calculations demonstrate that the conceivable Ph group shift occurs in the oxidized Co^III intermediate [{Sn^IVPh₂Cl₂}(κO₂N₂-μ-L){Co^III(MeO)}] (5) rather than in the corresponding Co^II species [{Sn^IVPh₂Cl₂}(κO₂N₂-μ-L){Co^II(MeOH)}] (4). Their catalytic studies in the Baeyer-Villiger oxidation of cyclohexanone into ε-caprolactone with two different oxidants reveal that the sacrificial aldehyde method (with dioxygen/benzaldehyde) is better than that with aqueous H₂O₂ (30%). The effects of various reaction parameters such as solvent, catalyst amount, temperature, time and heating method were studied allowing the achievement of yields up to 83% with 89% selectivity.

A novel 2-D Mn selenidostannate(iv) incorporating high-nuclear Mn clusters with spin canting behavior

A solvothermal reaction of SnCl₄·5H₂O, Mn and Se in ethanolamine (Hea) yielded a novel 2-D Mn selenidostannate(iv) [Mn₇(ea)₆(SnSe₄)₂]_n (1), which not only provides the first example of the incorporation of a hepta-nuclear Mn cluster [Mn₇(ea)₆]⁸⁺ into a selenidostannate(iv) framework, but also shows unusual spin canting behavior.

In situ ligand exchange-mediated 0D/1D transformation of a polyoxovanadate

The antimonato-polyoxovanadate {Ni^II(en)₃}₃[VIV15SbIII6O₄₂(H₂O)]·ca.15H₂O was utilized as a synthon for the solvothermal in situ generation of the new compound {Ni^II(phen)₃}₂[{Ni^II(en)₂}VIV15SbIII6O₄₂(H₂O)]·19H₂O, a rearrangement induced by ligand metathesis.

N-HO and N-HCl supported 1D chains of heterobimetallic CuII/NiII-SnIV cocrystals

The Schiff base H₂L¹ [N,N'-ethylenebis(3-methoxysalicylaldimine)] or H₂L² [N,N'-ethylenebis(3-ethoxysalicylaldimine)] was reacted with MCl₂·xH₂O and SnCl₄·5H₂O to afford the supramolecular heterobimetallic systems (H₂ED)²⁺·2[ML]·[SnCl₆]^2- [M = Cu, L = L¹ (1), L = L² (2); M = Ni, L = L¹ (3), L = L² (4); ED = 1,2-ethylenediamine], whose structures were established by single crystal X-ray analyses. Each structure includes different entities, viz. a mononuclear [CuL]/[NiL] neutral complex (coformer), a hexachlorostannate dianion [SnCl₆]^2-, a 1,2-ethylenediammonium dication (H₂ED²⁺) and, only in 2 and 4, a methanol molecule. Based on the work of Grothe et al. (Cryst. Growth Des., 2016, 16, 3237-3243), compounds 1 and 3 are cocrystal salts, 2 and 4 are cocrystal salt solvates. The ionic pairs (H₂ED)²⁺·[SnCl₆]^2- in 1-4 are encapsulated by the Cu- or Ni-complexes, and stabilized by N-HO and one N-HCl bond interactions leading to infinite 1D chains. The antimicrobial studies of 1-4 against yeasts (C. albicans and S. cerevisiae) and Gram-positive (S. aureus and E. faecalis) and -negative bacteria (P. aeruginosa and E. coli) indicate that the Ni₂Sn systems (3 and 4) are more active than the analogous Cu₂Sn ones (1 and 2).

Room-Temperature Synthesis of Thiostannates from {[Ni(tren)]2[Sn2S6]}n

The compound {[Ni(tren)]2[Sn2S6]}n (1) (tren = tris(2-aminoethyl)amine, C6H18N4) was successfully applied as source for the room-temperature synthesis of the new thiostannates [Ni(tren)(ma)(H2O)]2[Sn2S6]·4H2O (2) (ma = methylamine, CH5N) and [Ni(tren)(1,2-dap)]2[Sn2S6]·2H2O (3) (1,2-dap = 1,2-diaminopropane, C3H10N2). The Ni-S bonds in the Ni2S2N8 bioctahedron in the structure of 1 are analyzed with density functional theory calculations demonstrating significantly differing Ni-S bond strengths. Because of this asymmetry they are easily broken in the presence of an excess of ma or 1,2-dap immediately followed by Ni-N bond formation to N donor atoms of the amine ligands thus generating [Ni(tren)(amine)](2+) complexes. The chemical reactions are fast, and compounds 2 and 3 are formed within 1 h. The synthesis concept presented here opens hitherto unknown possibilities for preparation of new thiostannates.

Room temperature synthesis, crystal structure and selected properties of the new compound [Mn2(bipy)4SbS4](ClO4)

The new compound [Mn2(bipy)4SbS4](ClO4) was prepared by a new synthetic route for the preparation of thioantimonates(V) that can be used even at room temperature. Mixing aqueous solutions of [Mn(bipy)3](ClO4)2 and Na3SbS4 · 9H2O leads to immediate crystallization of the pure compound. In the structure an SbS4 3– anion acts as a tetradentate bridge connecting two Mn2+ cations of [Mn(bipy)3]2+ complexes (bipy = 2,2′-bipyridine). The compound features a hitherto unknown [Mn2(bipy)4SbS4]+ cation. Bipy ligands of adjacent cations are arranged parallel to each other leading to weak off-center parallel π-π interactions stabilizing the crystals. Magnetic measurements indicate weak antiferromagnetic exchange interactions between the Mn2+ centers.

Supramolecular hexagonal nano tubes assembled by vanadium diamine complexes with thiogermanates

A supramolecular hexagonal nano tube is characterized, which is assembled by oxo-vanadium thiogermanate in a sulfur–diamine reduction system.

A simultaneous disulfide bond cleavage, N,S-bialkylation/N-protonation and self-assembly reaction: syntheses, structures and properties of two hybrid iodoargentates with thiazolyl-based heterocycles

Unprecedented multiple in situ reactions were found during preparation of hybrid iodoargentates.

Utilization of mixtures of aromatic N-donor ligands of different coordination ability for the solvothermal synthesis of thiostannate containing molecules

Utilization of mixtures of differently coordinating aromatic N-donor ligands leads to the formation of the two new compounds {[Ni(phen)2]2Sn2S6}·4,4'-bipy·½H2O I and {[Ni(phen)2]2Sn2S6}·2,2'-bipy II that could be prepared under solvothermal conditions (4,4'-bipy = 4,4'-bipyridine, C10H8N2; phen = 1,10-phenanthroline, C12H8N2; 2,2'-bipy = 2,2'-bipyridine, C10H8N2). In the structures of both compounds Ni-S bond formation is observed which is highly unusual when only bidentate N-donor ligands are applied in the reaction mixture. The detailed analysis of the crystal structure indicates that the presence of 4,4'-bipy and 2,2'-bipy molecules are essential for the stabilization of the arrangement of the constituents. The main structural motif {[Ni(phen)2]2Sn2S6} is arranged generating off center parallel stacking of the phen ligands. The empty spaces between the {[Ni(phen)2]2Sn2S6} moieties are occupied by either 2,2'-bipy (I) or 4,4'-bipy (II) molecules which are oriented towards the phen ligands to form intermolecular π-π interactions.

Mononuclear and three-dimensional metal complexes based on a multidentate hydrazone ligand

A potentially pentadentate hydrazone ligand,N′-[1-(pyrazin-2-yl)ethylidene]nicotinohydrazide (HL), was prepared from the condensation reaction of nicotinohydrazide and acetylpyrazine. Reactions of HLwith MnCl2, Mn(CH3COO)2and Cd(CH3COO)2afforded three metal complexes, namely dichlorido{N′-[1-(pyrazin-2-yl-κN1)ethylidene]nicotinohydrazide-κ2N′,O}manganese(II), [MnCl2(C12H11N5O)], (I), bis{N′-[1-(pyrazin-2-yl-κN1)ethylidene]nicotinohydrazidato-κ2N′,O]manganese(II), [Mn(C12H10N5O)2], (II), and poly[[(acetato-κ2O,O′){μ3-N′-[1-(pyrazin-2-yl-κ2N1:N4)ethylidene]nicotinohydrazidato-κ3N′,O:N1}cadmium(II)] chloroform disolvate], {[Cd(C12H10N5O)(CH3COO)]·2CHCl3}n, (III), respectively. Complex (I) has a mononuclear structure, the MnIIcentre adopting a distorted square-pyramidal coordination. Complex (II) also has a mononuclear structure, with the MnIIcentre occupying a special position (C2symmetry) and adopting a distorted octahedral coordination environment, which is defined by two O atoms and four N atoms from twoN′-[1-(pyrazin-2-yl)ethylidene]nicotinohydrazidate (L−) ligands relatedviaa crystallographic twofold axis. Complex (III) features a unique three-dimensional network with rectangular channels, and theL−ligand also serves as a counter-anion. The coordination geometry of the CdIIcentre is pentagonal bipyramidal. This study demonstrates that HL, which can act as either a neutral or a mono-anionic ligand, is useful in the construction of interesting metal–organic compounds.

[Mn2Ga4Sn4S20]8− T3 supertetrahedral nanocluster directed by a series of transition metal complexes

Three new manganese gallium tin sulfides based on T3 supertetrahedral nanocluster of [Mn₂Ga₄Sn₄S₂₀]⁸⁻ have been solvothermally synthesized and structurally characterized. The photocatalytic, second-order nonlinear optical and luminescence properties, as well as thermal stabilities of the title compounds were also studied.