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1.
Chemistry ; : e202401656, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969621

RESUMO

Adamantane-type organotin sulfide clusters were recently shown to react with coinage metal phosphine complexes under replacement of an organic substituent by a metal-phosphine unit. An extension of such studies involving the silicon-based congener [(PhSi)4S6] (A) revealed that the cluster core will be partly disassembled and a {PhSi} moiety is replaced by a coinage metal phosphine complex to form [(Et3PAg)3(PhSi)3S6] (B) and [Na2(thf)2.33][(Me3PCu)(PhSi)3S6] (C). Herein, we present an extension of this work upon variation of the reactants and reaction conditions. Besides the isolation of crystalline precursor complexes [CuCl(PMe2Ph)3] (1) and [AgCl(PMe2Ph)2]2 (2), the study addresses reactions of A with AgCl and a phosphine ligand in CH2Cl2, upon which A is completely disassembled to form [(Ph3P)3Ag(µ-S)SiCl2Ph] (3). In another case a CH2 group, most likely stemming from CH2Cl2, was attached to the ligand, thus generating [{PhCl(S)SiSCH2P(Ph2)CH2CH2}2] (4). Upon using CuCl and 1,4­bis(diphenylphosphino)butane (dppb) we isolated the phosphine-bridged analog of B, [{(dppbCu2)CuP(Ph2)(CH2CH2)(PhSi)3S6}2] (5). In order to receive the yet elusive silver homolog of C, we used PMe2Ph as a bulkier ligand. This way we generated a 2D coordination polymer of the desired composition, [Na2(thf)1.5][(Me2PhPAg)(PhSi)3S6] (6). UV-visible spectra of 6 indicated a bandgap of 3.89 eV, thus blue-shifted in regards to B and C.

2.
Chem Sci ; 15(25): 9438-9509, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38939157

RESUMO

The research into adamantane-type compounds has gained momentum in recent years, yielding remarkable new applications for this class of materials. In particular, organic adamantane derivatives (AdR4) or inorganic adamantane-type compounds of the general formula [(RT)4E6] (R: organic substituent; T: group 14 atom C, Si, Ge, Sn; E: chalcogenide atom S, Se, Te, or CH2) were shown to exhibit strong nonlinear optical (NLO) properties, either second-harmonic generation (SHG) or an unprecedented type of highly-directed white-light generation (WLG) - depending on their respective crystalline or amorphous nature. The (missing) crystallinity, as well as the maximum wavelengths of the optical transitions, are controlled by the clusters' elemental composition and by the nature of the organic groups R. Very recently, it has been additionally shown that cluster cores with increased inhomogeneity, like the one in compounds [RSi{CH2Sn(E)R'}3], not only affect the chemical properties, such as increased robustness and reversible melting behaviour, but that such 'cluster glasses' form a conceptually new basis for their use in light conversion devices. These findings are likely only the tip of the iceberg, as beside elemental combinations including group 14 and group 16 elements, many more adamantane-type clusters (on the one hand) and related architectures representing extensions of adamantane-type clusters (on the other hand) are known, but have not yet been addressed in terms of their opto-electronic properties. In this review, we therefore present a survey of all known classes of adanmantane-type compounds and their respective synthetic access as well as their optical properties, if reported.

3.
J Org Chem ; 89(11): 7353-7354, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38801183
4.
Org Lett ; 26(22): 4581-4582, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38801189
5.
Inorg Chem ; 63(23): 10453-10454, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38801179
6.
Inorg Chem ; 63(21): 9670-9675, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38580311

RESUMO

Investigating the interactions of f-block metal ions with p-block polyanions in multinary cluster compounds is becoming increasingly attractive but remains a challenge in terms of both the synthetic approach and the control of the structures that are formed during the syntheses. So far, two types of reactions were dominant for the formation of corresponding clusters: the reaction of binary anions of p-block elements in 1,2-diamino-ethane (en) solutions or the reaction of organobismuth compounds with corresponding f-block metal complexes in THF. Herein, we report the synthesis of [La@In2Bi11]4- (1) and its doubly µ-Bi-bridged analogue in the doubly [K(crypt-222)]+-coordinated {[K(crypt-222)]2[La@In2Bi11](µ-Bi)2[La@In2Bi11]}4- (2) as their [K(crypt-222)]+ salts [K(crypt-222)]41 and [K(crypt-222)]42, respectively, achieved by reactions of [InMes3] and [La(C5Me4H)3] (Mes = mesityl, C5Me4H = tetramethylcyclopentadienyl) with K10Ga3Bi6.65/crypt-222 (crypt-222 = 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) in en. In the absence of [La(C5Me4H)3], the otherwise unchanged reactions afford the anions [Bi6(InMes)(InMes2)]3- (3) and [Mes3In-InMes3]2- (4) instead, which can be isolated as their [K(crypt-222)]+ salts [K(crypt-222)]33 and [K(crypt-222)]24·tol (tol = toluene), respectively. The {Bi6} fragment observed in anion 3 is assumed to be one of the key intermediates not only toward the formation of 1 and 2 but also on the way to more general bismuth rich compounds.

7.
Inorg Chem ; 62(51): 20859-20860, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38063311
8.
Chem Commun (Camb) ; 59(88): 13171-13174, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37850229

RESUMO

Chalcogenido metalate compounds that are based on tetrahedral clusters have been extensively studied in recent years due to their rich structural chemistry and uncommon chemical and physical properties. Recently it was shown that partial butylation of the inorganic cluster core by ionothermal reactions allowed access to tetrahedral sulfido-oxo stannate clusters with reasonable solubility in conventional solvents at the retainment of their opto-electronic features. We have expanded this mild alkylation approach, and herein report success in receiving the first sulfido-oxo stannate clusters that are selectively propylated, pentylated, and hexylated. This was achieved in a unique way by preparing symmetrically 1,3-substituted imidazolium bromides in preparative scale and using them as both the reaction medium and alkylatoin reagent. We discuss the effect of the organic groups attached to the cluster and present in the counterions of the products on the compounds' structural and opto-electronic properties.

10.
Inorg Chem ; 62(38): 15358-15366, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37703452

RESUMO

We introduce Na2[Fe3S4], comprising anionic layers, synthesized by a simple and straightforward solid-state method based on the fusion of binary sulfides of abundant sodium and iron. The structure crystallizes in a trigonal lattice with honeycomb cavities, as well as 25% of statistical iron vacancies in the crystal structure. The compound depicts high dielectric constants from 998 to 1850 at a frequency of 1 kHz depending on the sintering temperature, comparable with benchmark dielectric materials. According to the complex electrochemical impedance results, the compound depicts an electrical conductivity at ambient temperature. Optical investigations reveal a band gap of 1.64 eV, which is in agreement with an electronic band gap of 1.63 eV computed by density functional theory calculations. Magnetometry results reveal an antiferromagnetic behavior with a transition at 120 K. These findings introduce Na2[Fe3S4] as a sustainable multifunctional material with potential for a variety of electronic and magnetic applications.

11.
Inorg Chem ; 62(34): 13943-13952, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37581490

RESUMO

The selective methylation and butylation of chalcogenido metalate clusters by utilizing imidazolium-based ionic liquids turned out to be not only a comparably mild but at the same time also the only known method for postsynthetic alkylation of such species in order to increase their solubility. For additional impact on the crystal structures, selective alkylation with longer alkyl chains was addressed by utilizing the ionic liquid (C10C1Im)[BF4] (C10 = decyl group at position 1 and C1 = methyl group at position 3 of the cation's Im = imidazolium ring) for ionothermal syntheses of functionalized tellurido mercurate clusters. Herein, we report three novel compounds, two of which comprise cluster anions that exhibit a selective organic functionalization of their terminal telluride ligands upon in situ alkylation with the ionic liquid: [Hg6Te6(Te2)2(TeDec)2]6- (in 1; Dec = decyl) represents the first decylated chalcogenido metalate cluster. A unique heteroleptic functionalization, combining methylation and decylation, was achieved for the second cluster, [Hg6Te6(Te2)2(TeDec)(TeMe)]6- (in 2; Me = methyl). The third cluster is purely inorganic, but based on the same cluster core architecture: [Hg4Te2(Te2)2(Te3)2]4- (in 3) comprises a tritelluride unit instead of two HgTeR groups (R = Me, Dec). As a consequence of the long alkyl chains, both at the cluster and at the charge-compensating cations, all three crystal structures are characterized by lamellar assemblies of cations and anions. For further comparison of the properties of the organometallic versus purely inorganic compounds, vibrational and optical properties of crystalline samples of the compounds comprising clusters 1 and 3 were studied by means of infrared, Raman, and UV-visible spectroscopy. The results clearly show the effect of the presence of an organic decoration (in 1) relative to its absence (in 3), reflected by a red shift of the band gap energy (1 → 3) and a replacement of the Te-C bands (in 1) with bands for tritelluride units (in 3).

12.
Inorg Chem ; 62(36): 14505-14506, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37624367
13.
Commun Chem ; 6(1): 109, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37277548

RESUMO

Multimetallic clusters play a key role as models to doped metals, as candidates to new types of superatomic catalysts and as precursors to new multimetallic solids. Understanding formation pathways is an essential and necessary step forward in the development of cluster synthesis and research, yet remains considerably lacking owing to difficulty in identification of intermediates and the ill-defined nature of common starting materials. Here we show progress in this regard by investigating the reactivity of an intermetallic solid of nominal composition 'K5Ga2Bi4' with [W(cod)(CO)4] upon extraction with ethane-1,2-diamine (en) and 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane (crypt-222). Several polybismuthide intermediates and by-products were identified along the reaction pathway, ultimately forming the new polybismuthide salt [K(crypt-222)]3[µ:η3-Bi3{W(CO)3}2]∙en∙tol. DFT calculations revealed plausible reaction schemes for the transformations taking place in the reaction mixture providing insight into the complex reactivity of 'K5Ga2Bi4' on the basis of in situ generation of Bi22-.

16.
Angew Chem Int Ed Engl ; 62(23): e202303037, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37040132

RESUMO

Pseudo-tetrahedral units of p-block atoms proved to be excellent building blocks for novel molecular architectures and for introducing new elemental combinations which are not otherwise accessible. In this work, we present a series of clusters obtained by reactions of binary Ge/As anions with [MPh2 ] (M=Zn, Cd, Hg; Ph=phenyl). The study is grounded on the fact that the binary reactant gained by extracting the solid 'K2 GeAs' with ethane-1,2-diamine (en) co-exists as (Ge2 As2 )2- and (Ge3 As)3- in solution. This allows for a larger variety of products by 'selecting' the most suitable species for the final ternary complex to crystallize. The reactions afforded the unprecedented first step of the corresponding interaction, thus attachment of (MPh)+ to a pseudo-tetrahedral unit in [PhZn(Ge3 As)]2- (1) and [PhHg(Ge3 As)]2- (2), and complex anions with two, three, or four units, [(Ge3 As)Zn(Ge2 As2 )]3- (3), [Cd3 (Ge3 As)3 ]3- (4), and [Zn3 (Ge3 As)4 ]6- (5). Quantum chemistry confirmed the compositions and the positions of the Ge or As atoms, beside explaining structural peculiarities. The subtle impact of different [MR2 ] reactants was additionally studied by corresponding reactions using [ZnMes2 ] (Mes=mesityl), which showed success in selectively crystallizing [MesZn(Ge3 As)]2- (6). Based on our findings, we derive a suggestion of the underlying reaction cascade.

17.
Acc Chem Res ; 56(9): 1018-1030, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37067095

RESUMO

ConspectusBismuth-based research has become a highly topical field in recent years, yielding remarkable prospects for new fundamental insights and new materials applications, ranging from innovative catalysts to novel pharmaceuticals, due to this heavy metal's virtually nonradioactive and nontoxic properties. Given that the 6s2 electron pair can be stereochemically active under certain circumstances, bismuth atoms adopt a variety of coordination modes and bonding environments with oxidation states ranging from (formally) +V to -III. As a consequence, bismuth-based compounds cover the entire spectrum from simple coordination compounds to much more unusual cluster cations and cluster anions exhibiting metal-metal bonding in a homoatomic manner, or in concert with other s-, d-, p-, or f-block metal atoms. Such bismuth clusters show high potential for the development of new bismuth-based materials, but they are also interesting objects by themselves. Given the relatively recent development of bismuth-rich cluster molecules, a deep understanding of their properties─including unprecedented structural features, complex electronic structures, substantial heavy metal aromaticity, as well as their formation pathways─is still in its infancy. The topic thus spans a broad range from highly sophisticated synthetic chemistry through interdisciplinary experimental and theoretical analyses to materials science.Based on our recent work and several notable reports from other groups, this article will highlight the successful access to a number of novel bismuth-rich cluster ions emerging from both solution-based approaches and solid-state chemistry. It will shed light on the unique structural and electronic properties that cause chemical and physical peculiarities of such compounds. Selected examples include, but are not limited to, (1) the first encapsulation of actinide ions in intermetalloid clusters which additionally served to manifest substantial all-metal π-aromaticity with a (calculated) record ring current per electron; (2) a large metalloid {Zn12} unit stabilized in a porphine-related {Zn8Bi16} moiety in [K2Zn20Bi16]6-; (3) the largest assembly of bismuth atoms within one molecule, observed in [{Ru(cod)}4Bi18]4- that consists of two Bi-Bi-linked "[{Ru(cod)}2Bi9]2-" subunits.Notably, cluster growth has remained largely a black box, which is starting to be revealed, however. We discuss possible formation pathways of such (multi)metallic nanoarchitectures on the basis of smaller subunits that were detected by mass spectrometric analyses and could also be captured upon reaction with organometallic complexes. In addition to the intrinsic structural and electronic properties of the cluster anions and cluster cations reviewed herein, we will briefly introduce the emerging usage of bismuth-based compounds in material science and give an outlook to future developments.

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