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This study introduces a sustainable and pioneering cascade synthesis of 1,3‐thiazolidine derivatives under eco‐friendly conditions. The methodology transcends traditional approaches yielding complex novel compounds with unique N,S‐heterocyclic structures. By operating at room temperature, utilizing green solvents, and minimizing excess of reactants, this procedure offers an innovative pathway for sustainable chemical development. Notably, this method not only prioritizes sustainability but also delivers high‐purity products with exceptional yields. The simplicity of the process, requiring only a simple filtration and featuring short reaction times, underscores its efficiency and utility. [ABSTRACT FROM AUTHOR]

The combination of the ferrocene moiety with gold(I) catalysis remains a relatively unexplored field. In this article, we delve into the synthesis, characterization, and potential catalytic activity of four complexes utilizing both monodentate and bidentate ferrocenyl diphenylphosphane ligands (ppf and dppf), coordinated with two gold(I) metal centers, linked by either chloride or pentafluorophenylthiolate bridging ligands. This leads to the formation of cationic "self‐activated" precatalysts capable of initiating the catalytic cycle without the need for external additives. The catalytic activity of these complexes was assessed through a model reaction in gold(I) catalysis, specifically the cyclization of a N‐propargylbenzamide to produce an oxazole. In addition, we studied and compared the influence exerted by both the phosphane and the bridging ligand on the performance of these catalysts. [ABSTRACT FROM AUTHOR]

Gold(II) complexes, unlike their gold(I) and gold(III) counterparts, have been sparsely employed in the field of catalysis. This is primarily due to the challenges associated with isolating and characterising these open-shell species. However, these complexes offer a wide range of possibilities. On one hand, this intermediate oxidation state has proven to be more easily accessible through reduction and oxidation processes compared to the gold(I)/gold(III) redox couple, thereby facilitating potential homo-coupling and cross-coupling reactions. On the other hand, gold(II) exhibits Lewis acid behaviour, bridging the characteristics of the soft acid gold(I) and the hard acid gold(III). In this review, we focus on mono- and dinuclear gold(II) complexes, whether they are isolated and well-studied or proposed as intermediates in cross-coupling reactions induced by the action of oxidants or light. We delve into the unique reactivity and potential applications of these gold(II) species, shedding light on their role in this field. This comprehensive exploration aims to underscore the latent promise of gold(II) complexes in catalysis, offering insights into their structural and mechanistic aspects while highlighting their relevance in contemporary chemical transformations. [ABSTRACT FROM AUTHOR]

Silver complexes bearing substituted terpyridine or tetra‐2‐pyridinylpyrazine ligands have been prepared and structurally characterised. The study of the anticancer properties of silver complexes with this type of ligands is scarce, despite the possibilities of combining the properties of the metal and the ability of the ligands for DNA binding. Here, the antiproliferative activity, stability, CT‐DNA binding, and mechanism of cell death of these types of derivatives are studied. High cytotoxicity against different tumour cells was observed, and, more important, a great selectivity index has been detected between tumour cells and healthy lymphocytes T for some of these compounds. The CT‐DNA interaction study has shown that these derivatives are able to interact with CT‐DNA by moderate intercalation. Furthermore, cell death studies indicate that these derivatives promote the apoptosis by a mitochondrial pathway. [ABSTRACT FROM AUTHOR]

Trigonal planar coordination at gold allows phosphorescent 3MC transitions, not expected for luminescent mononuclear linear gold complexes. The careful selection and nature of the ancillary ligands bonded to gold, being fluorophore groups or not emissive ligands may cause a distortion of ideal trigonal planar coordination favoring different origins for the emissions. Consequently, intraligand (IL) or charge transfer (CT) transitions may be present and besides the expected phosphorescent MC transitions, fluorescence or thermally activated delayed fluorescence (TADF) may be the origin of the luminescence. In addition of the advantages of triplet population and deactivation via phosphorescent or delayed fluorescence processes, these systems are very versatile and may show interesting properties such as mechanochromism and vapochromism and, consequently, have revealed as promising candidates for optical applications. The objective of this review is to provide an overview of the reported luminescent three‐coordinated gold systems and to get insight into their emissive properties. [ABSTRACT FROM AUTHOR]

A new class of emissive cyclometallated IrIII−AuI complexes with a bis(diphenylphosphino) methanide bridging ligand was successfully synthesised from the diphosphino complex [Ir(N^C)2(dppm)]+ (1). The different gold ancillary ligand, a triphenylphosphine (2), a chloride (3) or a thiocytosine (4) did not reveal any significant effect on the photophysical properties, which are mainly due to metal‐to‐ligand charge‐transfer (3MLCT) transitions based on IrIII. However, the AuI fragment, along with the ancillary ligand, seemed crucial for the bioactivity in A549 lung carcinoma cells versus endothelial cells. Both cell types display variable sensitivities to the complexes (IC50=0.6–3.5 μM). The apoptotic pathway is activated in all cases, and paraptotic cell death seems to take place at initial stages in A549 cells. Species 2–4 showed at least dual lysosomal and mitochondrial biodistribution in A549 cells, with an initial lysosomal localisation and a possible trafficking process between both organelles with time. The bimetallic IrIII−AuI complexes disrupted the mitochondrial transmembrane potential in A549 cells and increased reactive oxygen species (ROS) generation and thioredoxin reductase (TrxR) inhibition in comparison with that displayed by the monometallic complex 1. Angiogenic activity assays performed in endothelial cells revealed the promising antimetastatic potential of 1, 2 and 4. [ABSTRACT FROM AUTHOR]

A new type of asymmetric binuclear Zn(II) complex was synthesized from a suitable mononuclear precursor. One Zn(II) was coordinated to a salphen ligand (salphen = N,N′-disalicylidene-1,2-phenylenediamine) and the other to a modified salphen bearing OC12H25 chain in the 4,4' positions, the two being joined by phenylene rings. The molecular structure, determined by DFT calculations (ADF/BP86(COSMO:THF)/TZ2P), showed the non-planarity of each of the two complexes, the dihedral angle at the junction being ∼36°. The absorption spectra of 2 and its precursor 1 in DMSO showed a strong band in the visible at 427 and 408 nm, respectively, assigned based on TDDFT calculations mainly to intra- and interligand π→π* transitions. Complex 2 displayed emission at 531 nm in DMSO and 534 nm in other solvents. The long alkyl chain of its substituents promoted self-assembly of these amphiphilic molecules. No gels were formed in DMSO, but several bands (420, 418 and 480 nm) and shoulders appeared in other solvents, and gels were detected when increasing concentration. The formation of aggregates was studied by scanning electron microscopy and atomic force microscopy, and the images found in the three solvents reflected different supramolecular arrangements. These studies revealed that the binuclear compound formed stable gels above 8.88 mM for tetrahydrofuran and 13.3 mM for toluene and chloroform. [ABSTRACT FROM AUTHOR]

This article, titled "Front Cover: Ferrocenyl Dinuclear Gold(I) Complexes. Study of their Structural Features and the Influence of Bridging and Phosphane Ligands in a Catalytic Cyclization Reaction," explores the use of bridging ligands in the synthesis of ferrocenyl gold(I) dinuclear complexes. The cover image features a ferrocene reflecting on the moon surface, symbolizing the connection between two gold metal centers. Two dragons represent different bridging ligands and their resulting structures. The article highlights the importance of these bridging ligands in catalytic reactions, particularly in cyclization reactions. The full research article can be found in Chemistry - A European Journal by Juan Carlos Pérez‐Sánchez, Raquel P. Herrera, and M. Concepción Gimeno. [Extracted from the article]

This review covers the advances made in the synthesis of luminescent transition metal complexes containing N-heterocyclic carbene (NHC) ligands. The presence of a high field strength ligand such as an NHC in the complexes gives rise to high energy emissions, and consequently, to the desired blue colour needed for OLED applications. Furthermore, the great versatility of NHC ligands for structural modifications, together with the use of other ancillary ligands in the complex, provides numerous possibilities for the synthesis of phosphorescent materials, with emission colours over the entire visible spectra and potential future applications in fields such as photochemical water-splitting, chemosensors, dye-sensitised solar cells, oxygen sensors, and medicine. [ABSTRACT FROM AUTHOR]

A selected group of cationic three-coordinate Au(I)-NHC complexes of the form [Au(NHC)(dppbz)]OTf have been prepared from a commercially available bidentate phosphine. All complexes have been fully characterised by NMR and mass spectroscopy. The [Au(NHC)]+ fragment shows a pronounced tendency to form linear complexes which is confirmed by the molecular structure of [Au(IPr)(dppbz)]OTf in the solid state. The complexes are brightly luminescent and present very high quantum yield values in the solid state. The assignments of the electronic transitions involved in the emissions are of a phosphorescent nature and it is proposed that the origin of the emissions is derived from the ligand (dppbz) to metal-ligand (Au-NHC) charge-transfer (LML'CT) transition. [ABSTRACT FROM AUTHOR]

Abstract: The reactions between five ferrocenyl derivatives containing both a Cleast an imidazole or pyridine nitrogen atom and AgPF6, AgOTf, or [Cu(NCCH3)4]PF6 precursors were studied. The ligand {[bis(2-pyridyl)amino]carbonyl}ferrocene (L3), derived from (2-pyridyl)amine, favored tetrahedral coordination of Ag+ (with two ligands) and of Cu+ (with two acetonitrile ligands left from the precursor). In all the other ligands, both metal centers coordinated linearly to two ligands, preferring the imidazole or pyridinic nitrogen to other nitrogen atoms (amine) or oxygen donors. When the counter anions were triflate, the crystal structure showed a dimerization of the complex, with the ferrocenyl moieties occupying cis positions, by means of a weak Ag⋯Ag interaction. This was shown experimentally in the crystal structure of complex [Ag(L1)2]OTf (L1=ferrocenyl imidazole) and in the presence of peaks corresponding to {Ag2(L2)3(OTf)}+ and {Ag2(L2)4(OTf)}+ in the mass spectra of [Ag(L2)2]OTf (L2=ferrocenyl benzimidazole). In all complexes containing PF6, there was no evidence for dimerization. Indeed, in the crystal structure of [Ag(L2)2]PF6, the ferrocenyl moieties occupy trans positions and the metal centers are far from each other. DFT calculations showed that the energy of the cis and trans conformers is practically the same and the balance of crystal packing forces leads to dimerization when triflate is present. [Copyright &y& Elsevier]

The ligand 1,1 .bis[N,N′-(2-diphenylphosphino) amide]ferrocene, Fc(CONHCH2CH2PPh2)2 (L), has been synthesized by reaction of the chioro carbonyl derivative Fc(COCI)2 and the aminophosphine NH2CH2CH2PPh2. The coordination properties towards silver(l), goldQ) and gold(lll) compounds have been explored. Several complexes with the diphosphine acting as bidentate chelating or bridgind ligand have been prepared. Furthermore the dinuclear species [Au2{Fc(CONCH2CH2PPh2)2}] with the ligand coordinated through the phosphorus and the deprotonated amido group have been achieved. [ABSTRACT FROM AUTHOR]

The synthesis and X-ray analysis of complexes [(μ-1,12-C2B10H10){Au(PPh3)}2] and [(μ-1,2-C2B10H10)- {Au(PMe3)}2] have provided the experimental data needed to analyse two points. The first point is the use of these data to carry out a computational study with the aim of comparing the electronic structures and relative stabilities of the organometallic isomers [(μ-1,n-C2B10H10){Au(PR3)}2] (n = 2, 7, 12; R = Ph, Me) with those of the parent carborane clusters ortho-, meta- and para-carborane and the influence of the monophosphine substituents. The second point is focused in the influence of the steric demand of the monophosphine in the presence or not of aurophilic interactions in the ortho derivatives [(μ-1,2-C2B10H10){Au(PR3)}2] (R= Me, Ph). The photoluminescent behaviour of both the carboranes and the organometallic complexes is presented. [ABSTRACT FROM AUTHOR]

The article cites a study which presents an overview of the results in the synthesis and reactivity of chalcogen-centered derivatives. Most of the work were developed with sulfur and selenium, and had been divided according to the nuclearity of the bridging chalcogenide ligands. The findings obtained with sulfur and selenium are very similar.

These ligands may or may not be emissive, but their selection, together with different distortions from the ideal geometry around the gold atom, leads to luminescent three-coordinated complexes with different emission energies. Coordination modes, Fluorescence, Gold, Luminescence, Phosphorescence, Three-coordinated, TADF Keywords: Coordination modes; Fluorescence; Gold; Luminescence; Phosphorescence; Three-coordinated; TADF EN Coordination modes Fluorescence Gold Luminescence Phosphorescence Three-coordinated TADF 3912 3912 1 10/26/21 20211014 NES 211014 B The Front Cover b shows different ligands with phosphorus, nitrogen, carbon, or other donor atoms, used as building blocks for the construction of three-coordinated gold(I) complexes. [Extracted from the article]

[2-(Me2NCH2)C6H4]HgCl (1) was prepared by reacting HgCl2 with [2-(Me2NCH2)C6H4]Li in diethyl ether. The reactions of 1 with the sodium or ammonium salt of the appropriate thiophosphinato ligand, in 1:1 molar ratio, afford the isolation of [2-(Me2NCH2)C6H4]Hg[S(S)PR2] [R=Me (2), Et (3), Ph (4)], [2-(Me2NCH2)C6H4]Hg[S(O)PPh2] (5) and [2-(Me2NCH2)C6H4]Hg[S(S)P(OiPr)2] (6). The compounds were investigated by IR and multinuclear NMR (1H, 13C and 31P) spectroscopy. The molecular structures of 1 and 4 were determined by single-crystal X-ray diffraction. Due to the strong intramolecular coordination of the N atom of the pendant CH2NMe2 arm [Hg(1)–N(1) 2.764(6) and 2.725(4) A˚ in 1 and 4, respectively] both compounds exhibit a T-shaped (C,N)HgX core in the molecular unit, with almost linear arrangement of the covalent bonds [C(1)–Hg(1)–Cl(1) 176.93(18)° in 1, and C(1)–Hg(1)–S(1) 169.54(16)° in 4]. The crystals of 1 contain discrete monomeric molecules, while the crystals of 4 contain dimer associations built through asymmetric bridging dithiophosphinato ligands [Hg(1)–S(1) 2.3911(16) A˚, Hg(1)⋯S(2a) 3.102(2) A˚], thus resulting in an overall pseudo-trigonal bipyramidal (or seesaw) (C,N)HgS2 core, with the nitrogen atom and the weekly bonded sulfur atom in equatorial positions [N(1)–Hg(1)⋯S(2a) 82.01(10)°]. [Copyright &y& Elsevier]