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In this paper, we describe a series of diphenylphosphane and diphenylphosphanide gold(III) and gold(III)/gold(I) complexes containing 3,5-C6Cl2F3 as aryl ligands at gold that have been synthesized due to the arylating and oxidant properties of the new polymeric thallium(III) complex [TlCl(3,5-C6Cl2F3)2]n (1). Its reaction with [Au(3,5-C6Cl2F3)(tht)] (tht = tetrahydrothiophene) produces the gold(III) complex [Au(3,5-C6Cl2F3)3(tht)] (2), which allows the synthesis of the diphenylohosphane derivative [Au(3,5-C6Cl2F3)3(PPh2H)] (3). Its treatment with acetylacetonate gold(I) derivatives leads to two novel AuIII/AuI phosphanido-bridged complexes, [PPN][Au(3,5-C6Cl2F3)3(µ-PPh2)AuCl] (4) and [PPN][{(3,5-C6Cl2F3)3Au(µ-PPh2)}2Au] (5). All these complexes have been characterized, and the crystal structures of 1, 2, 4 and 5 have been established by single crystal X-ray diffraction methods, showing a novel polymeric arrangement in 1. [ABSTRACT FROM AUTHOR]

The assembly of two different building blocks, [{Au(C6F5)2}{PbCl(terpy)}] (terpy=2,2′:6′:2′′‐terpyridine) and [{Au(C6F5)2}2{Pb(terpy)}]n, acting as terminal or central pieces, respectively, gives rise to a decanuclear complex built via metallophilic and π‐stacking interactions in which the number of AuI⋅⋅⋅AuI and AuI⋅⋅⋅PbII contacts is finely controlled. [ABSTRACT FROM AUTHOR]

The assembly of two different building blocks, [{Au(C6F5)2}{PbCl(terpy)}] (terpy=2,2′:6′:2′′‐terpyridine) and [{Au(C6F5)2}2{Pb(terpy)}]n, acting as terminal or central pieces, respectively, gives rise to a decanuclear complex built via metallophilic and π‐stacking interactions in which the number of AuI⋅⋅⋅AuI and AuI⋅⋅⋅PbII contacts is finely controlled. [ABSTRACT FROM AUTHOR]

The reactivity of the heterometallic polynuclear complexes [{Au(R)2}2Cu2(MeCN)2]n (R=C6F5, C6Cl5) with the thioether crowns 1,4,7‐trithiacyclononane (L1, [12]aneS3), 1,4,8,11‐tetrathiacyclododecane (L2, [14]aneS4), 1,4,7,10,13,16,19,22‐octathiacyclotetracosane (L3, [24]aneS8), and the quinoline functionalized pendant arm derivatives of the 12‐membered mixed‐donor macrocycles 1‐aza‐,4,7,10‐trithiacyclododecane ([12]aneNS3) and 1,7‐diaza‐4,10‐dithiacyclododecane ([12]aneN2S2), L4 and L5, respectively, was investigated in THF solution. While with L4 and L5 only ionic compounds of general formulation [Cu(L)][Au(R)2] were isolated and structurally characterized (none of them featuring Au⋅⋅⋅Cu interactions), with L1‐L3, beside similar ionic compounds, some heteronuclear complexes of general formulation [{Au(R)2}{Cu(L)}] and featuring Au⋅⋅⋅Cu interactions were also obtained. All of them display rather unusual non‐classical C−H⋅⋅⋅Au hydrogen interactions. The complexes display in the solid state different optical properties related to their structures, which have been studied experimentally and theoretically via TD‐DFT calculations. In particular, all compounds of the type [{Au(R)2}{Cu(L)}] featuring Au⋅⋅⋅Cu metallophilic interactions display luminescence in the solid state both at room temperature (RT) and at 77 K. On the contrary, ionic compounds of general formulation [Cu(L)][Au(R)2], except [Cu(L4)][Au(C6F5)2], are not luminescent. [ABSTRACT FROM AUTHOR]

The ionic complex [Au(9N-adenine)(PMe3)](CF3CO2) (1) displays a supramolecular structure built up through ionic, π-stacking, C–H…O, C–H…N and C–H…Au interactions. Ab initio calculations permit the characterization of the nature of these interactions. Complex 1 is luminescent in the solid state at 77 K. This complex forms a hydrometallogel consisting of straight molecular nanowires, which is responsive to thermal and mechanical stimuli. The gel has also been studied by rheological oscillatory experiments. [ABSTRACT FROM AUTHOR]

Following an acid–base strategy, based on the reaction between gold(i) basic fragments and acid silver salts, it is possible to obtain heterometallic polymers of the general formula [Au2Ag2(R)4(L)2]n (R = C6Cl2F3; L = pyrimidine). Using this new heterometallic complex [Au2Ag2(C6Cl2F3)4(pym)2]n (1) as a starting material, and a good coordinating solvent such as acetonitrile, it is possible to modify the arrangement of the ligands connected to the silver centres and to obtain three different tetranuclear Au2Ag2 building blocks leading to the new polymer [Au6Ag6(C6Cl2F3)12(μ2-pym)2(NCMe)6]n (2). Both complexes display very intense luminescence emission. Structural, experimental and computational studies have been carried out in order to identify the origin of these properties and the factors that can affect them, such as, the presence of metallophilic interactions as well as different coordination environments for the metallic centres. [ABSTRACT FROM AUTHOR]

The structure of the complex [{Pb(HBpz3)}{Au3(o-C6BrF4)3(HBpz3)}] consists of a host–guest heterometallic system built up through a plethora of interactions including electrostatic, metallophilic, H-bonding, Au…Br or weak C…C or Pb…Br contacts. Computational studies show that the dispersive interactions are responsible for the attraction of the Pb(ii) cationic moiety within the basket-like trinuclear Au(i) fragment, whereas the ionic component of the interaction placed at the rings produces a molecular clamp. [ABSTRACT FROM AUTHOR]

Among the coinage metal complexes displaying luminescent properties, those bearing C-donor aryl ligands have an increasing part in the chemistry of these metals. These types of ligands confer a high kinetic and thermodynamic stability on the complexes, but they can also be involved in the photoluminescent behaviour of the complexes. The development of new aryl-containing complexes of group eleven metals, the study of their photoluminescent properties and their related properties and applications are discussed in this perspective. Among these, luminescent gold(i) and gold(iii) compounds are being intensively used for the development of new properties with potential applications such as, for instance, electroluminescence, triboluminescence, mechanochromism, aggregated induced emissions, quenching, luminescent liquid crystals, low molecular weight gelators and photocatalysts, among others. [ABSTRACT FROM AUTHOR]

The preparation of homoleptic heterometallic complexes still remains a challenge. Herein, we report the synthesis and characterization of [Au(PMe3)2][{AuHg2(o-C6F4)3}{Hg3(o-C6F4)3}] (1), a gold–mercury homoleptic metallacycle. The crystal structure of 1 displays two [Hg2M(o-C6F4)3] (M = AuI, HgII) units linked through a short Au…Hg contact of 3.097(2) Å, the strongest unsupported AuI…HgII interaction described to date. Theoretical calculations quantify the interaction between the trimetalic units as −199 kJ mol−1, a surprisingly strong value. [ABSTRACT FROM AUTHOR]

Different [AuL]+ fragments (L = tertiary phosphines, ylides, or NHC carbene) have been tested under mild conditions as suitable catalysts for the transformation of terminal or internal alkynes into the corresponding cyclic acetals upon reaction with ethylene glycol. We have obtained a moderate to negligible activity when using tertiary phosphines or nonstabilized ylides as ligands. However, a very high catalytic activity is reached when the IPr N-heterocyclic carbene ligand is used. We have analyzed the key stages in this type of gold-catalyzed reaction, namely, (i) electronic activation (alkynophilicity); (ii) protodeauration; and (iii) decomposition of the gold catalyst. The first two stages have been analyzed through DFT computation of the minimum-energy reaction pathways employing different catalysts. An explanation of the catalysts' stability has been proposed through the analysis of in situ time-resolved nuclear magnetic resonance spectra of the catalysts. [ABSTRACT FROM AUTHOR]

The tetrahedral AuI complexes [Au(GeCl3)L3] (L=PMe3 ( 1), PMe2Ph ( 2), PMePh2 ( 3), PPh3 ( 4)) were synthesized by in situ treatment of the [Au(GeCl3)(tht)] complex with three equivalents of the corresponding tertiary phosphine. The crystal structures of complexes 1 and 3 have been determined through X-ray diffraction studies and show [GeCl3]− fragments bonded to the corresponding [Au(PR3)3]+ units through covalent bonds, leading to a tetrahedral coordination environment for gold. Complexes 3 and 4 show dual phosphorescence in the solid state at 77 K and, in the case of complex 4, an interesting room-temperature mechanochromism effect is observed. Correlated MP2, SCS-MP2, SCS-CC2, and ONIOM MP2/UFF calculations suggest the existence of two largely distorted and thermally connected triplet excited states (T1 and T2) for a model system of complex 4. The AuP3+ moiety can be distorted in two different planes leading to the two triplet excited states T1 and T2, leaving the GeCl3− unit almost unaltered. The emissions of these phosphorescent AuIGeII complexes is mainly ascribed to a metal (gold)-centered (3MC) transition with some contribution from the [GeCl3]− fragments. [ABSTRACT FROM AUTHOR]

Ultrathin Au–Ag alloy nanorods and nanowires of different lengths and ca. 1.9 nm diameter are prepared through a low-temperature decomposition of the precursor [Au2Ag2(C6F5)4(OEt2)2]n in oleic acid. This nanostructure formation has been studied through TEM, HRTEM, EDS, HS-SPME-GC-MS and 19F NMR spectroscopy. The UNRs and UNWs display a length-dependent broad band in the mid-IR region that is related to the longitudinal mode of the surface plasmon resonance of the ultrathin nanostructures. [ABSTRACT FROM AUTHOR]

Reaction of [Au(C6F5)(tht)] (tht = tetrahydrothiophene) with 2,2′:6′,2″-terpyridine (terpy) leads to complex [Au(C6F5)(η¹-terpy)] (1). The chemical oxidation of complex (1) with 2 equiv of [N(C6H4Br-4)3](PF6) or using electrosynthetic techniques affords the Au(III) complex [Au(C6F5)(η³-terpy)](PF6)2 (2). The X-ray diffraction study of complex 2 reveals that the terpyridine acts as tridentate chelate ligand, which leads to a slightly distorted square-planar geometry. Complex 1 displays fluorescence in the solid state at 77 K due to a metal (gold) to ligand (terpy) charge transfer transition, whereas complex 2 displays fluorescence in acetonitrile due to excimer or exciplex formation. Time-dependent density functional theory calculations match the experimental absorption spectra of the synthesized complexes. In order to further probe the frontier orbitals of both complexes and study their redox behavior, each compound was separately characterized using cyclic voltammetry. The bulk electrolysis of a solution of complex 1 was analyzed by spectroscopic methods confirming the electrochemical synthesis of complex 2. [ABSTRACT FROM AUTHOR]

The reactions of 4(dimethylamino)pyridine (DMAP) with the gold(i) precursors [AuR(tht)] (R = C6F5, C6Cl2F3 or C6Cl5; tht = tetrahydrothiophene) lead to complexes [AuR(DMAP)] (R = C6F5 (1), C6Cl2F3 (2) or C6Cl5 (3)). X-ray diffraction studies of the complexes reveal the presence of discrete molecules in which aurophilic contacts are absent, with π-stacking (1) or hydrogen bond (2) interactions being responsible for the supramolecular arrangements found in the solid state. All complexes display fluorescence in solution in solvents of different polarities such as toluene, chloroform or acetonitrile. In all cases the emission energy is similar to the low-energy Twisted Intramolecular Charge Transfer (TICT) emission of free DMAP. TDDFT calculations confirm that the fluorescence of complexes 1–3 arises from the ICT excited state of bonded DMAP in which a 90° distortion of the pyridine ring and –NMe2 planes is observed. Model calculations based on experimental parameters show a higher degree of polarization of DMAP upon coordination to Au(i) organometallic fragments. [ABSTRACT FROM AUTHOR]

Heteronuclear complexes[HgM(o-C6H4PPh2)2]X (M = Au, X = ClO4(1); M = Ag,X = BF4(2); M= Ag, X = CF3CO2(3); M = Cu, X= Br (4)) were prepared by the treatment of [Hg(o-C6H4PPh2)2] with one equivalent of the corresponding coinage metal salt. Theircrystal structures, determined by X-ray diffraction methods, displayHgII···MI(M = Au, Ag, Cu) contacts. Ab initiocalculations show similar interaction energies(ca. 40 kJ·mol–1) and similar origin (dispersiveforces) for these Hg···Au, Hg···Ag,and Hg···Cu interactions. [ABSTRACT FROM AUTHOR]

Two different theoretical approaches have been used for the description of the experimentally observed dual luminescence of 4-(dimethylamino)pyridine (DMAP), introducing solvent effects with the polarizable continuum model (PCM), which seems needed to represent the dual fluorescence in polar media. These approaches are the linear response time-dependent density functional theory (TDDFT) and the state-specific complete active space self-consistent field. Both levels of theory represent the expected planar high-energy and the twisted intramolecular charge transfer (ICT) low-energy excited-state structures in the presence of solvent (toluene and acetonitrile). The comparison between both approaches shows that the main distortion of the ICT state is similar for both cases, i.e. twisting to almost 90º of the pyridine ring and the dimethylamino planes, but that other secondary distortions are slightly different. In the case of the TDDFT approach, the geometry optimizations of DMAP in the ground and excited states have been carried out using the conventional linear response approach (LR-PCM) for the solvent inclusion. The LR-PCM and the specific state (SS-PCM) approaches have been used for the prediction of the excitation and emission energies of DMAP in toluene and acetonitrile. The prediction of the emission energies at TDDFT/LR-PCM and CASPT2/PCM (complete active space perturbation theory) levels agrees with the experimental ones. [ABSTRACT FROM AUTHOR]

Reactions between [Au(C6Cl2F3)(tht)] and P,N-donor bridging ligands of the type PPh2py and (PPh2)2phen lead to the homonuclear gold complexes [Au(C6Cl2F3)(PPh2py)] (1) and [Au2(C6Cl2F3)2{(PPh2)2phen}] (2). Subsequent addition of [Cu(CH3CN)4](BF4) leads to the formation of the corresponding gold-copper heterometallic complexes [Au2Cu(C6Cl2F3)2(PPh2py)2](BF4) (3) and [Au2Cu(C6Cl2F3)2{(PPh2)2phen)}-(CH3CN)](BF4) (4). The four complexes have been structurally characterized and are luminescent. The gold precursors show emissions arising from metal-perturbed intraligand transitions. The heterometallic complexes show a red shift of the emissions that is proposed to arise from an admixture of IL (intraligand) and MLCT (metal-to-ligand-charge-transfer) transitions. DFT and TD-DFT calculations agree well with these results. [ABSTRACT FROM AUTHOR]

Two organometallic complexes, named [Hg(2-C6H4PPh2)2] (1) and [{Au(C6F5)}2{Hg(2-C6H4PPh2)2}] (2) have been studied as quenchers of the fluorescence of naphthalene. Positive deviations were observed in the Stern-Volmer (S-V) plots for both quenchers. The analyses of the data reveal the existence of transient components in the dynamic quenching. The diffusion coefficients of these complexes have been obtained by two different methods, through the Stokes-Einstein equation, and from ¹H PGSE NMR experiments. With these values, and taking into account the experimental KT constants, the radii of the transient quenching spheres were obtained, which show unusually large values. [ABSTRACT FROM AUTHOR]

MoS2 nanoflowers (NFs) obtained through a hydrothermal approach were used as the substrate for the deposition of tiny spherical bimetallic AuAg or monometallic Au nanoparticles (NPs), leading to novel photothermal-assisted catalysts with different hybrid nanostructures and showing improved catalytic performance under NIR laser irradiation. The catalytic reduction of pollutant 4-nitrophenol (4-NF) to the valuable product 4-aminophenol (4-AF) was evaluated. The hydrothermal synthesis of MoS2 NFs provides a material with a broad absorption in the Vis-NIR region of the electromagnetic spectrum. The in situ grafting of alloyed AuAg and Au NPs of very small size (2.0–2.5 nm) was possible through the decomposition of organometallic complexes [Au2Ag2(C6F5)4(OEt2)2]n and [Au(C6F5)(tht)] (tht = tetrahydrothiophene) using triisopropilsilane as reducing agent, leading to nanohybrids 1–4. The new nanohybrid materials display photothermal properties arising from NIR light absorption of the MoS2 NFs component. The AuAg-MoS2 nanohybrid 2 showed excellent photothermal-assisted catalytic activity for the reduction of 4-NF, which is better than that of the monometallic Au-MoS2 nanohybrid 4. The obtained nanohybrids were characterised by transmission electron microscopy (TEM), High Angle Annular Dark Field—Scanning Transmission Electron Microscopy—Energy Dispersive X-ray Spectroscopy (HAADF-STEM-EDS), X-ray photoelectron spectroscopy and UV-Vis-NIR spectroscopy. [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]

Tetrahedral Au¹ complexes [L3Au(SnCl3)l (L = PMe3 (1), PMe2Ph (2), PMePh2 (3), and PPh3 (4)) were prepared by treatment of the [(tht)Au(SnCl3)l (tht = tetrahydrothiophene) complex with three equivalents of the corresponding tertiary phosphine. The crystal structures of complexes 1-4 have been determined through X-ray diffraction studies showing, in all cases, [SnCl3]-fragments covalently bonded to the corresponding [Au(PR3)3]+ units, which leads to a tetrahedral coordination environment for gold. Complexes 3 and 4 show phosphorescence in the solid state at room temperature and 77 K that is largely redshifted relative to the free [Au(PR3)3]+ and [SnCl3]- counterparts. Correlated MP2, SCS-MP2, and ONIOM MP2/UFF calculations suggest a largely distorted lower triplet excited state (T,) for each model system. The AuP3+ moiety is distorted leading to a T-shape, whereas the SnCl3- unit is left almost unaltered. Molecular orbital and population analysis suggest that the emission of these tetrahedral Au1 complexes arises from a ³MC transition slightly perturbed by the SnCl3- fragment. [ABSTRACT FROM AUTHOR]

Heteronuclear complexes {[Hg(R)2][Au(R′)(PMe3)]2} n (R=R′=C6Cl2F3 ( 3); R=R′=C6F5 ( 4); R=C6Cl2F3, R′=C6F5 ( 5); R=C6F5, R′=C6Cl2F3 ( 6)) were prepared by the treatment of the corresponding organomercury compounds, [Hg(C6X5)2], with two equivalents of [Au(C6X5)(PMe3)]. Their crystal structures, as determined by using X-ray diffraction methods, display Au⋅⋅⋅Hg interactions. Although only compound 4 and 5 show luminescence in the solid state, all of these compounds quench the fluorescence of naphthalene in solution. Solution studies of these derivatives suggest a cooperative effect of the gold(I) center in switching on the quenching capabilities of the [Hg(C6X5)2] synthon with naphthalene. Theoretical studies confirmed the quenching ability of the organomercury species in the presence of gold. [ABSTRACT FROM AUTHOR]

The synthesis, structural characterization, and studyof the photoluminescentproperties of the complexes [Au3Cu(C6F5)4(NCCHCHPh)3]n(1) and [Au2Cu(C6Cl5)3(NCCHCHPh)2] (2) have been carried out. The crystal structuresof complexes 1and 2display a common [Au2Cu(C6X5)2(μ-C6X5)(NCCHCHPh)2] fragment built up through atrinuclear Au2Cu unit with a perhalophenyl group actingas a three-center–two-electron bridging ligand. In the caseof 1an additional [Au(C6F5)(NCCHCHPh)]unit is also present in the asymmetric unit. Both complexes are brightlyluminescent in the solid state at room temperature and at 77 K withlifetimes in the nanosecond range for 1and in the microsecondrange for 2. The presence of very short metallophilicinteractions seems to be responsible for the low-energy luminescenceobserved. DFT and time-dependent DFT calculations agree with the experimentalresults and support the idea of that the origin of the emissions arisesfrom metal-based orbitals and arrive at ligand-based orbitals as chargetransfer transitions. [ABSTRACT FROM AUTHOR]

By reaction of the heterometallic gold-silver complexes [{AuAg(C6F5)2(N≡C-Me)}2]n or [{AuAg(C6Cl5)2(N=C-Me)}2]n and CuCl in the presence of pyrimidine and different nitrile ligands (acetonitrile, benzonitrile, and cinnamonitrile), the heteronuclear complexes {[Au(C6X5)2][Cu(L)(μ2-C4H4N2)]}n (X = F and L = N≡C-Me (1), L = N≡C-Ph (2) or N≡C-CH-CH-Ph (3); X = Cl and L = N≡C-Me (4), N≡C-Ph (5), N≡C-CH-CH-Ph (6)) have been prepared. The crystal structures of complexes {[Au(C6X5)2][Cu(L)(μ2-C4H4N2)]}n (X = F; L = N≡C-CH-CH-Ph (3), X = Cl; L = N≡C-Ph (5)) have been determined by X-ray diffraction studies. The crystal structures of both complexes consists of polymeric chains formed by the repetition of [Au(C6X5)2][Cu(L)(μ2-C4H4N2)] units through copper-pyrimidine bonds. Complexes 1, 2, 4, and 5 are brightly luminescent in the solid state at room temperature and at 77 K with lifetimes in the microseconds range. These compounds are also luminescent in solution, displaying different photophysical behaviors depending on the donor characteristics of the solvents used. The distortion in the excited state allows an associative attack by donor solvents quenching one of the emitting excited states. DFT optimizations of the ground (S0) and lowest triplet excited state (T1) display the structure distortion of the complexes upon electronic excitation. The molecular orbitals involved in the electronic transitions responsible for the phosphorescence in the case of the complexes 1, 2, 4, and 5 are related to metal (gold-copper) to ligand (pyrimidine) charge transfer transitions, while in the case of the nonluminescent complexes 3 and 6, the nonradiative electronic transition arises from metal (gold-copper) to ligand (cinnamonitrile) charge transfer transitions. [ABSTRACT FROM AUTHOR]

Abstract: The (perhalophenyl)tin derivatives [SnR4] (1–3) and [SnR3Cl] (4–6) (R=C6F5, C6F3Cl2, C6Cl5) were prepared from SnCl4 and LiR or [SnR4] in the appropriate molar ratio, while the dinuclear complexes [SnR3]2 (7–9) were obtained by treatment of [SnR3Cl] with potassium under toluene reflux. Complexes 2, 6·0.5toluene and 7 were structurally characterized, the latter displaying a Sn–Sn bond of 2.808(7)Å, which indicates a strong tin–tin bond with covalent character in solid state. The hexaaryldistannanes 7–9 undergo transmetallation reactions with gold(I) derivatives, such as [AuCl(PPh3)] or [(AuCl)2(μ-dppm)], affording the neutral species [AuR(PPh3)] (10–12) or [(AuR)2(μ-dppm)] (13–15) or the ionic product [Au3Cl2(μ-dppm)2][Sn(C6F5)3Cl2] (16). The crystal structures of 14·CH2Cl2, 15 and 16·2CH2Cl2 were determined by X-ray diffraction, the latter showing a Au3 nearly equilateral triangular core in the cation with gold–gold contacts of 3.128(7) and 3.227(12)Å. The main difference between the molecular structures of 14·CH2Cl2 and 15 (both of them displaying intramolecular gold–gold contacts of 3.142(6) and 3.160(4)Å, respectively) is the presence of an intermolecular Au⋯Au interaction of 3.2126(8)Å in the case of the C6F3Cl2 complex that gives rise to a tetranuclear unit. [Copyright &y& Elsevier]

The vapochromic behaviors of {Ag2L2[Au(C6F5)2]2}n (L = Et2O (1), Me2CO (2), THF (3), CH3CN (4)) were studied. {Ag2L2[Au(C6F5)2]2}n (L = Et2O (1)) was synthesized by the reaction of [Bu4N][Au(C6F5)2] with AgOClO3 in 1:1 molar ratio in CH2Cl2/Et2O (1:2). 1 was used as starting material with THF to form (Ag2L2[Au(C6F5)2]2}n (L = THF (3)). 3 crystallizes in the monoclinic space group C2/c and consists of tetranuclear units linked together via aurophilic contacts resulting in the formation of a 1D polymer that runs parallel to the crystallographic z axis. The gold(l) atoms are linearly coordinated to two pentafluorophenyl groups and display additional Au ⋯ Ag close contacts within the tetranuclear units with distances of 2.7582(3) and 2.7709(3) Å. Each silver(I) center is bonded to the two oxygen atoms of the THF molecules with a Ag-O bond distance of 2.307(3) Å. TGA analysis showed that 1 loses two molecules of the coordinated solvent per molecular unit (1st one: 75-100°, second one: 150-175 °C), whereas 2, 3, and 4 lose both volatile organic compounds (VOCs) and fluorinated ligands in a less well defined manner. Each complex loses both the fluorinated ligands and the VOCs by a temperature of about 325 °C to give a 1:1 gold/silver product. X-ray powder diffraction studies confirm that the reaction of vapors of VOCs with 1 in the solid state produce complete substitution of the ether molecules by the new VOC. The VOCs are replaced in the order CH3CN > Me2CO > THF > Et2O, with the ether being the easiest to replace. {Ag2(Et2O)2[Au(C6F5)2]2}n and {Ag2(THF)2[Au(C6F5)2]2}n both luminesce at room temperature and at 77 K in the solid state. Emission maxima are independent of the excitation wavelength used below about 500 nm. Emission maxima are obtained at 585 nm (ether) and 544 nm (THF) at room temperature and at 605 nm (ether) and 567 nm (THF) at 77 K. [ABSTRACT FROM AUTHOR]

By treatment of the polymeric species [AuTI(C6Cl5)2] n with ketones or with acetylacetone and 4,4′-bipyridine, the new tetranuclear complexes [Au2TI2(C6Cl5)4]·L (L = PhMeC=O, acacH) or [Au2TI2(C6Cl5)4 (bipy)]·(acacH) have been prepared. Their crystal structures have been determined by X-ray diffraction methods and they all present a central Au2TI2 core formed via one TI···TI and four Au···TI unsupported interactions resulting in a loosely bound butterfly cluster. These complexes are strongly luminescent in both the solid state and solution showing an optical behavior in agreement with the maintenance of the TI···TI contact even in solution. [ABSTRACT FROM AUTHOR]

Discusses the use of aurophilic and hydrogen bonding in the self-assembly of phosphine of diphosphine complexes of gold with the thiolate ligands derived from 2-thiobarbituric acid by deprotonation. Reaction of gold trifluoroacetate complexes; Synthesis and spectra of the complexes; Structure of the cyclic compound.

The formation and characterization of dinuclear gold(I) dialkyl- and diaryl-dithiophosphinate complexes of the type [AuS[sub 2] PR[sub 2] ][sub 2] are described. The complexes are readily prepared from the reaction between a chloro–gold(I) starting material and the corresponding dithiophosphinate salt. The structures of the complexes show both the absence (R = Et, 1) and presence (R = Ph, 2a) of intermolecular Au···Au interactions as confirmed by X-ray crystallographic study in the solid state. Reaction between [AuS[sub 2] PPh[sub 2] ][sub 2] and [Au(CH[sub 2] )[sub 2] PMe[sub 2] ][sub 2] in CH[sub 2] Cl[sub 2] solution leads to a ligand transfer reaction to form the hetero-bridged complex [Au[sub 2] {(CH[sub 2] )[sub 2] PMe[sub 2] S[sub 2] PPh[sub 2] }] (3a) in high yield. Additionally, the latter complex reacts with Cl[sub 2] to form the oxidative addition product [Au[sub 2] Cl[sub 2] {(CH[sub 2] )[sub 2] PMe[sub 2] S[sub 2] PPh[sub 2] }] (4), the first gold(II) complex with a S-P-S bridging moiety. The X-ray crystal structure of both 3a and 4 exhibit rare boat conformations in the solid state, and 4 has a formal Au(II)—Au(II) single bond of 2.5611(5) Å. Reaction between [AuS[sub 2] PPh[sub 2] ][sub 2] and dppm (dppm = Ph[sub 2] PCH[sub 2] PPh[sub 2] ) leads to a sparsely soluble three-coordinate dinuclear gold(I) complex with the molecular formula [Au[sub 2] {dppmS[sub 2] PR[sub 2] }[sub 2] ][sub n] (n = 1 or ) (5).Key words: dithiophosphinates, ylide, dithiols, gold-gold bond.On décrit la préparation et la caractérisation de complexes dinucléaires de dialkyl- et diaryldithiophosphinates d'or(I), du type [AuS[sub 2] PR[sub 2] ][sub 2] . Les complexes se forment facilement par réaction d'un produit de départ contenant du chloro-or(I) avec le sel de dithiophosphinate correspondant. Les structures des complexes montrent dans un cas l'absence (R = Et, 1) et dans l'autre la présence (R = Ph, 2a) d'interactions Au···Au intermoléculaires qui ont été confirmées par une étude cristallographique par diffraction des rayons X à l'état solide. La réaction entre le [AuS[sub 2] PPh[sub 2] ][sub 2] et le [Au(CH[sub 2] )[sub 2] PMe[sub 2] ][sub 2] , en solution dans le CH[sub 2] Cl[sub 2] , donne lieu à une réaction de transfert de ligand qui conduit à la formation, avec un rendement élevé, du complexe hétéroponté [Au[sub 2] {(CH[sub 2] )[sub 2] PMe[sub 2] S[sub 2] PPh[sub 2] }], 3a. De plus, ce dernier complexe réagit avec le Cl[sub 2] pour former le produit d'addition oxydante [Au[sub 2] Cl[sub 2] {(CH[sub 2] )[sub 2] PMe[sub 2] S[sub 2] PPh[sub 2] }], 4, le premier complexe d'or(II) comportant un pont S-P-S. Les structures de diffraction des rayons X des produits 3a et 4 montrent toutes les deux la présence de conformations bateaux, rares à l'état solide; de plus, le produit 4 comporte aussi une liaison simple Au(II)—Au(II) de 2,5611(5)Å. La réaction du [AuS[sub 2] PPh[sub 2] ][sub 2] avec le dppm (dppm = Ph[sub 2] PCH[sub 2] PPh[sub 2] ) conduit à la formation d'un complexe d'or(I) dinucléaire, tricoordiné et à peine soluble de formule moléculaire [Au[sub 2] {dppm]{S[sub 2] PR[sub 2] }[sub 2] ][sub n] (n = 1 ou ), 5.Mots clés : dithiophosphinates, ylure, dithiols, liaison or-or.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The heteronuclear AuI/HgII complexes [Hg{AuR(μ-2-C6H4PPh2)}2] [R = C6F5 (1), C6Cl2F3 (2)] were prepared by reacting [Hg(2-C6H4PPh2)2] with [AuR(tht)] (1:2) and further transformed into the AuIII/HgII species [Hg{Au(C6F5)Cl2(μ-2-C6H4PPh2)}2] [R = C6F5 (3), C6Cl2F3 (4)] by the addition of 2 equiv of PhI#lb Cl2. The crystal structures of 1--3 display Au-HgII interactions, which in the case of 3 is the first AuIII...Hg contact described to date. Theoretical calculations on model systems of the C6F5 derivatives evidence that the attraction between AuI or AuIII and HgII arise from dispersion-type interactions and that both contacts are of the same strength. [ABSTRACT FROM AUTHOR]

The one-electron oxidizing agent [NO]PF6wasreactedwith Bu4N[Au(C6X5)2] (X= F, Cl) complexes in CH3CN. The gold(III) complexes [Au(C6F5)3(CH3CN)] and cis-[Au(C6Cl5)2(CH3CN)2]PF6were synthesized by the oxidationof gold(I) to gold(III) with the concomitant ligand rearrangement“oxidative rearrangement”. The supramolecular crystalpacking in the perfluorinated aryl gold(III) complex is dictated bythe notably short C(sp2)–F···H(CH3CN) bond distance. The [Au(C6Cl5)2(CH3CN)2]PF6complex exhibitsantisymbiosis, displaying equal ligands in the cis position. The electrochemicaloxidation of Bu4N[Au(C6X5)2] (X = F, Cl) complexes in CH3CN showed two irreversiblepeaks at 0.71 and 1.21 V (X = F) and at 0.65 and 0.91 V (X = Cl) vsAg/AgCl. [ABSTRACT FROM AUTHOR]

Reaction of perhalophenylgold(I) complexes [AuR(tht)] (R = C 6 Cl 2 F 3 , C 6 Cl 5 ; tht = tetrahydrothiophene) with different number of equivalents of Xantphos (4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene) leads to discrete complexes in which the metal atom displays very different coordination environments. Thus, the ionic complex [Au(Xantphos) 2 [Au(C 6 Cl 2 F 3) 2 (1) or the neutral [Au(C 6 Cl 5)(Xantphos)] (2) one are obtained when a 1:1 (Au:Xantphos) stoichiometry is used. However, similar compounds [Au 2 R 2 (μ-Xantphos)] (R = C 6 Cl 2 F 3 (3); C 6 Cl 5 (4)) are synthesized when the amount of gold is increased to a 2:1 ratio. The use of diphosphine Xantphos, which can act as bridging, chelate or even as mono-dentate ligand, together with the use of different perhalophenyl groups bonded to the gold(I) centres, allows the synthesis of cationic tetracoordinate gold(I) fragments (1), mononuclear (2) or dinuclear (3 – 4) dicoordinated gold(I) complexes. This structural diversity in the coordination arrangements as well as the different aryl groups present in the molecules directly affect their photophysical properties, giving rise to different luminescent emission energies ranging from 470 to 580 nm, and also to a different origin for the electronic transitions related to them such as 3IL (3) to 3MLCT (4) and also a mixture of them 3MLCT/3IL (1 and 2). The experimental photophysical results obtained for these gold(I) complexes were supported by DFT and TD-DFT calculations. On the other hand, the behaviour of these complexes in solution is different, losing their emissive properties for all complexes or displaying the co-existence of different structural arrangements in the case of complexes 1 and 2 , as observed through variable-temperature 31P{1H} NMR experiments. Image 1 • The use of Xantphos expands the coordination abilities of gold(I) centres. • Controlling the structural arrangements permits a tuning of the emissive properties. • TD-DFT shows 3IL and/or 3MLCT transitions as responsible for the luminescence. [ABSTRACT FROM AUTHOR]

The reaction of the polymeric heterometallic compound [{Au(C6Cl5)2}Ag]n with the macrocyclic ligands 1‐aza‐4,7,10‐trithiacyclododecane (L1), 1,7‐diaza‐4,11‐dithiacyclododecane (L2), 1‐aza‐4,10‐dithia‐7‐oxacyclododecane (L3) in tetrahydrofuran (THF) and 1 : 1 reaction molar ratio affords the new Au(I)/Ag(I) complexes [{Au(C6Cl5)2}{Ag(L1)}] (1), [{Au(C6Cl5)2}{Ag(L2)}] (2), [{Au(C6Cl5)2}{Ag(L3)}] (3) and [{Au(C6Cl5)2}{Ag(L3)}]2 (4) that have been structurally characterized. Despite 1–3 show the same nature of binuclear complexes, only 3 changes its luminescence properties upon grinding as a consequence of partial amorphization. [ABSTRACT FROM AUTHOR]

The polymeric linear chain [AuTl(C6Cl5)2]n reacts with three terpyridine-type ligands substituted with thiophene groups containing N-donor centres in different relative positions (L1, L2 and L3), leading to the Au(I)/Tl(I) complexes [AuTl(C6Cl5)2(L1)]n (1), [{AuTl(C6Cl5)2}2(L2)]n (2) and [AuTl(C6Cl5)2(L3)]n (3). X-Ray diffraction studies reveal that L1 acts as a chelate, while L2 and L3 act as bridging ligands, resulting in different coordination indexes for the thallium(I) centre. These structural differences strongly influence their optical properties, and while compounds 2 and 3 emit near the limit of the visible range, complex 1 emits in the infrared region. DFT calculations have also been carried out in order to determine the origin of the electronic transitions responsible for their optical properties. [ABSTRACT FROM AUTHOR]

The synthesis of gold(III) and gold(I)–gold(III) complexes with phosphide bridges is still a matter that requires solutions for their marked instability, in spite of the affinity of this metal in both oxidation states for phosphorous donor ligands. In the course of our studies, we realized that the presence of perhalophenyl groups of the type pentafluorophenyl or 3,5-dichlorotrifluorophenyl in the complexes gives rise to an increase in their stability that eases their isolation and structural characterization. In this paper, we describe two new fully characterized neutral compounds of this type to extend the knowledge on this family of compounds, [{Au(C6Cl2F3)2}2(µ-PPh2)2] (1) and [{Au(C6Cl2F3)2(µ-PPh2)2Au}2] (2). In this work, we analyze the role of the perhalophenyl groups in the stability of these complexes by using quantum chemical topology methodologies, specifically employing an analysis of the non-covalent interactions (NCIs) in real space and evaluating the electrostatic potential surfaces (ESP). Our findings reveal the existence of appreciable π-stacking interactions among the perhalophenyl and phenyl groups in both compounds, significantly contributing to the stability of the systems. [ABSTRACT FROM AUTHOR]

The reaction among [Au2Ag2(C6F5)4(OEt2)2]n, PbCl2 and terpyridine leads to the polymeric complex [{Au(C6F5)2}2{Pb(terpy)}]n (1). Its crystal structure reveals potential voids close to the lead centres large enough to hold different molecules. The availability of these free sites allows complex 1 to act as a VOC sensor. Thus, when 1 is exposed to different solvent vapours such as acetonitrile, toluene or THF, variations in its solid appearance and its photophysical properties are observed as a consequence of the formation of the new polymorphs [{Au(C6F5)2}2{Pb(terpy)(CH3CN)2}]n (2), [{Au(C6F5)2}2{Pb(terpy)}]n·Tol (3) and [{Au(C6F5)2}2{Pb(terpy)(THF)}]n·THF (4). Each polymorph displays a different emission energy depending on its structure and the presence of metallophilic interactions. In addition, the reversible solvent molecule exchange allows the tuning of the luminescence emissions in the greenish yellow–red range. DFT and TD-DFT calculations were performed to explain the origin of the luminescence of all these complexes. [ABSTRACT FROM AUTHOR]

1,4,7-Triazacyclononane (TACN) has been used for the first time to support Au(I)⋯M [M = Tl(I), Ag(I)] metallophilic interactions in the formation of heteronuclear gold(I) complexes having luminescence properties. The compounds {[{Au(C6Cl5)2}Tl(TACN)]2}n (1), [{Au(C6F5)2}Tl(TACN)] (2), [{Au(C6Cl5)2}Ag(TACN)] (3), and [{Au(C6F5)2}{Ag(TACN)}2Au(C6F5)2] (4) have been synthesized by reacting TACN and the polymeric starting organometallic gold(I) compounds [{Au(C6X5)2}M]n (M = Ag(I), Tl(I); X = Cl, F) in a 1 : 1 molar ratio, in THF. 1, 3 and 4 have also been structurally characterized and their optical properties explained on the basis of their structural features with the support of TD-DFT calculations. [ABSTRACT FROM AUTHOR]

Au⋅⋅⋅H−X (X=N or C) hydrogen bonding is gaining increasing interest, both in the study of its intrinsic nature and in their operability in different fields. While the role of these interactions has been studied in the stabilization of gold(I) complexes, their role during the minimum free energy reaction pathway of a given catalytic process remains unexplored. We report herein that complex [Au(C≡CPh)(pip)] (pip=piperidine) catalyses the A3‐coupling reaction for the synthesis of propargylamines, thanks to the ability of Au(I) to promote weak hydrogen bonding interactions with the reactants along the free energy profile. Density Functional Theory (DFT) calculations show that these Au⋅⋅⋅H−X interactions play a directing role in the catalysed A3‐coupling. Topological non‐covalent interactions (NCI), interaction region indicator (IRI) and quantum theory of atoms in molecules (QTAIM) analysis in real space of the electron density provide a description of these interactions accurately. [ABSTRACT FROM AUTHOR]

Au⋅⋅⋅H−X (X=N or C) hydrogen bonding is gaining increasing interest, both in the study of its intrinsic nature and in their operability in different fields. While the role of these interactions has been studied in the stabilization of gold(I) complexes, their role during the minimum free energy reaction pathway of a given catalytic process remains unexplored. We report herein that complex [Au(C≡CPh)(pip)] (pip=piperidine) catalyses the A3‐coupling reaction for the synthesis of propargylamines, thanks to the ability of Au(I) to promote weak hydrogen bonding interactions with the reactants along the free energy profile. Density Functional Theory (DFT) calculations show that these Au⋅⋅⋅H−X interactions play a directing role in the catalysed A3‐coupling. Topological non‐covalent interactions (NCI), interaction region indicator (IRI) and quantum theory of atoms in molecules (QTAIM) analysis in real space of the electron density provide a description of these interactions accurately. [ABSTRACT FROM AUTHOR]

Aggregating gold(I) complexes in solution through short aurophilic contacts promotes new photoluminescent deactivation pathways (aggregation-induced emission, AIE). The time dependence of spontaneous AIE is seldom studied. We examine the behavior of complex [Au(N9-hypoxanthinate)(PTA)] (1) in an aqueous solution with the aid of variable-temperature NMR, time-resolved UV–Vis and photoluminescence spectroscopy, and PGSE NMR. The studies suggest that partial ligand scrambling in favor of the ionic [Au(PTA)2][Au(N9-hypoxanthinate)2] pair followed by anion oligomerization takes place. The results are rationalized with the aid of computational calculations at the TD-DFT level of theory and IRI analysis of the electron density. [ABSTRACT FROM AUTHOR]

The main results from the work of the authors, concerning the use of mixed thia/aza medium sized macrocycles for the development of optically selective fluorescent chemosensors for toxic heavy metals, and luminescent gold(I) complexes will be discussed. Particular attention will be paid to underline both the role played by these macrocyclic ligands in determining the properties of the systems developed and the structure/function relationships observed. [ABSTRACT FROM AUTHOR]

A temperature-controlled self-assembly process in a solution of [Ag(terpy)]nn+ and [Au(C6F5)2]− units has been performed. For this, the crystallisation of the complex [{Au(C6F5)2}Ag(terpy)]n under the same experimental conditions, changing only the temperature, allows the synthesis of polymorphs [{Au(C6F5)2}2Ag2(terpy)2]n (2a) at 298 K and [{Au(C6F5)2}Ag(terpy)]n (2b) at 280 K. The X-ray diffraction studies previously reported for 2a revealed a polymeric structure with an unusual + + −− + + −− charge sequence, whereas for polymorph 2b, a more classical + − + − disposition has been obtained. The conversion of one polymorph into the other can be achieved by simple dissolution of one of them and by recrystallisation at the corresponding temperature. The mechanism of the formation of each polymorph is proposed in view of their 1H NMR, 1H-PGSE NMR and molar conductivity measurements. [ABSTRACT FROM AUTHOR]

Abstract: The crystal structure of the polymeric complex [Au5Ag2Tl3(C6F5)10(L1)2]n (L1=1‐aza‐4,10‐dithia‐7‐oxacyclododecane) displays heterotrimetallic Ag⋅⋅⋅Au⋅⋅⋅Tl moieties and is held by unsupported metallophilic interactions. This complex emits at 500 nm in the solid state. Ab initio calculations show that the large thermodynamic stability that helps the formation of this heterotrimetallic system arises from the combination of dispersive forces and a very large dipole moment in the supramolecular arrangement. [ABSTRACT FROM AUTHOR]

Invited for this month's cover are collaborators from the group of José M. López-de-Luzuriaga at Universidad de la Rioja, Spain and researchers from University of Helsinki, Finland. The cover picture shows a photograph of a gold-germanium complex that has two emission modes corresponding to two independent triplet excited states. Read the full text of the article at . [ABSTRACT FROM AUTHOR]

The cover picture shows a photograph of a gold–germanium complex that has two emission modes corresponding to two independent triplet excited states. The figure also shows the computed excited‐state structures of the two triplets, which display double Jahn–Teller distortions at the gold and germanium centres. The difference between the structures arises from a “T”‐shaped distortion at the gold centre with a different orientation depending on the triplet state. This small difference leads to a dramatic change of luminescence colour from orange to blue. Details are given in the Full Paper by José M. López‐de‐Luzuriaga et al. on page 176 in Issue 2, 2016 (DOI: 10.1002/cplu.201500337). [ABSTRACT FROM AUTHOR]

Studies a luminescent, polymeric, semi-conducting gold-thallium complex with a solid-state structure that permits reversible interactions and related color changes with a variety of volatile organic compounds. Description of structural features; Shift of emission energy; Manifestation of a vapochromatic behavior.

Investigates the chemical reaction between gold and thallium (Th) precursors. Synthesis of the gold-heterometal complex; Interaction of the Th atoms with the oxygen atom of an acetone; Linear coordination of the gold centers with pentachlorophenyl groups.

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]

The reaction of the polymers [Au2Cu2(C6X5)4(NCMe)2]n (X = Cl (1), F (2)) with the aromatic N-donor ligand pyridazine in different molar ratios gives rise to new Au(i)/Cu(i) heterometallic complexes [AuCu(C6Cl5)2(μ2-C4H4N2)(NCMe)]2 (3), [AuCu(C6X5)2(μ2-C4H4N2)(C4H4N2)]2 (X = Cl (4), X = F (6)) and [Cu2(μ2-C4H4N2)3(NCMe)2][Au(C6F5)2]2 (5). In all cases, the close proximity of the donor atoms in the diazine ligand leads to discrete molecules where two copper centres are connected by two or three bridging pyridazine ligands. In this way, focusing on the number of bridging ligands present in the molecules, unsupported closed-shell Au(i)…Cu(i) (with two bridging pyrazine ligands) or weak Cu(i)…Cu(i) interactions (with three bridging pyridazines) have been observed. None of these pyridazine derivatives is luminescent, which is probably related to the absence of aurophilic contacts. [ABSTRACT FROM AUTHOR]

The existence of aurophilic gold(III)⋯gold(III) interactions has for a long time been neglected due to structural arguments and comparison with the aurophilicity of gold(I) compounds. We show with calculations at the CCSD(T) level of theory that the [AuIII(CH3)3(NH3)]2 dimer has a metallophilic dispersion interaction between the gold(III) atoms of 10.5 kJ mol−1. The aurophilic interaction is illustrated by topological QTAIM calculations and IRI analysis. [ABSTRACT FROM AUTHOR]