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The synthesis and isolation of [Ru(Cp)(PCy2NPh2)(=C=CHPh]PF6 and [Ru(Cp*)(PCy2NCy2)(=C=CHPh)]PF6 was successfully accomplished. Use of these ruthenium vinylidene complexes for stoichiometric reactions with a variety of amines was performed. Upon reaction with alkyl amines, deprotonation of the Cβ hydrogen resulted in formation of acetylide complex [Ru(Cp*)(PCy2NPh2)(−C≡CPh)], and the species was confirmed through independent synthesis. In contrast, reaction of the less basic aryl amine aniline with [Ru(Cp)(PCy2NCy2)(=C=CHPh)]PF6 resulted in outer sphere addition to give a Fischer carbene product. [ABSTRACT FROM AUTHOR]

Reactions of a dicopper(I) tert-butoxide complex with alkynes possessing boryl or silyl capping groups resulted in formation of unprecedented tetracopper(I) μ-acetylide/diyne complexes that were characterized by NMR and UV/Vis spectroscopy, mass spectrometry and single-crystal X-ray diffraction. These compounds possess an unusual μ4 -η1 :η1 :η1 :η1 coordination mode for the bridging organic fragment, enforced by the rigid and dinucleating nature of the ligand utilized. Thus, the central π system remains unperturbed and accessible for subsequent reactivity and modification. This has been corroborated by addition of a fifth copper atom, giving rise to a pentacopper acetylide complex. This work may provide a new approach by which metal-metal cooperativity can be exploited in the transformation of acetylide and diyne groups to a variety of substrates, or as a starting point for the controlled synthesis of copper(I) alkyne-containing clusters.

By reaction of sodium electride or NaC2H with the anhydrous sodium salt of propiolic acid, Na(OOC−C≡C−H), in liquid ammonia crystalline powders of Na2C3O2 were obtained. The structure analysis based on synchrotron powder diffraction data revealed that Na2C3O2 crystallizes in a monoclinic unit cell (I2/a, Z=4) exhibiting the elusive Y‐shaped −C≡C−COO− anion, which is unprecedented in a crystalline compound up to now. IR/Raman and solid‐state NMR spectroscopic investigations with assignments supported by DFT‐based ab initio calculations confirm this finding. Reaction with sodium electride led to a higher crystallinity of the product, but additionally a by‐product apparently due to decomposition and polymerization of Na2C3O2 was formed. No such by‐product was observed in the reaction with NaC2H, which turned out to be a milder metalation route. However, the product of the latter reaction is less crystalline. [ABSTRACT FROM AUTHOR]

• Acyclic aminooxy carbene (AAOC) ligands stabilize gold(I) acetylide (AAOC)Au(C CC 6 H 4 R) type complexes. • The (AAOC)Au(C CC 6 H 4 R) type complexes catalyzed Alkyne-Aldehyde-Amine (A3) coupling yielding propargylamines and amino indolizines. • The (AAOC)Au(C CC 6 H 4 R) based catalysts represent the first direct access of a catalytic intermediate in the A3 coupling catalysis. • The electronic structure and bonding characteristics of the 1-6 complexes as investigated using steric map plot analysis, 13C NMR analysis, and other supporting computational analyses, showed a robust concordance with the experimental data. • The rate-determining 1,2-intramolecular hydrogen atom transfer step is crucial for the formation of amino indolizine products. • The non-covalent Au•••H–C(alkyl) and Au•••H–C(aryl) interactions play a prominent role in the A3 coupling reaction. The gold(I) acetylide complexes of Acyclic Aminooxy Carbene (AAOC) ligands, [{(4-R1-2,6- t -Bu 2 -C 6 H 2 O)(NCy 2)}methylidene]Au[C C(p -C 6 H 4 R2)] [where R1 = H; R2 = H (1), and R1 = t -Bu; R2 = H (4)] efficiently catalyzed the three-component Alkyne-Aldehyde-Amine (A3) coupling yielding propargylamine and amino indolizine compounds, thereby implicating its direct role in the catalytic cycle. The DFT studies performed on a simplified gold(I) precatalyst, [{(2,4,6-Me 3 -C 6 H 2 O)(NCy 2)}methylidene]Au[C CPh] (4'), at B3LYP-D3/def2-TZVP of theory implicated the role of non-covalent Au•••H–C interactions in the A3 coupling reactions producing propargylamine and subsequently amino indolizine via intramolecular cyclization of propargylamine followed by an intramolecular 1,2-hydrogen transfer-step for the 2-formylpyridine substrate. The non-covalent Au•••H–C(alkyl) and Au•••H–C(aryl) interactions participate in tandem to influence the overall reaction kinetic barrier, and thereby illustrating the importance of such interactions in gold catalysis. The gold(I) acetylide complexes, [{(4-R1-2,6- t -Bu 2 -C 6 H 2 O)(NCy 2)}methylidene]Au[C C(p -C 6 H 4 R2)] [where R1 = H; R2 = H (1), Me (2), OPh (3): R1 = t -Bu; R2 = H (4), Me (5), OPh (6)] were conveniently synthesized from the corresponding chloro analogues [{(4-R1-2,6- t -Bu 2 -C 6 H 2 O)(NCy 2)}methylidene]AuCl (where R1 = H, t -Bu) by the treatment with terminal alkyne HC C(p -C 6 H 4 R2) (where R2 = H, Me, OPh) in the presence of K 2 CO 3 as a base in ca. 88−95 % yield. [Display omitted] Gold(I) acetylide acyclic aminooxy carbene complexes successfully catalyzed A3-coupling yielding propargylamine and amino indolizine compounds, and thereby implicating its role in the catalytic cycle. [ABSTRACT FROM AUTHOR]

Despite significant strides achieved in organic light emitting diode (OLED) based display technologies during the last decade, the search for highly stable and efficient true blue/deep blue emitters continues to remain elusive. During the past decade, emitters with the basic molecular scaffold consisting of Pt(II) acetylides and N‐heterocyclic carbene (NHC) ligands have opened interesting opportunities to tune the emission properties with desired chromaticity in the blue and deep blue region. With an aim to achieve the desired CIE coordinates along with low device roll‐off efficiencies and satisfactory color purity, a number of variations on the basic molecular fragment have been made. A number of NHC Pt(II) alkyne complexes bearing monodentate, bidentate and tridentate ligands have been synthesized and their photophysical investigations have been reported. Although NHC Pt(II) alkyne complexes have been explored in other areas of applications, much of the investigations have been primarily focused for their interesting emission properties appearing particularly in the shorter wavelength (450–495 nm) part of the electromagnetic spectrum for organic light emitting diode (OLED) devices. In this review, we provide an overview of the investigated NHC Pt(II) acetylide complexes by detailing their synthesis, luminescence properties, performance in devices and future perspectives. [ABSTRACT FROM AUTHOR]

Half‐sandwich rare‐earth dialkynyl complexes are of much interest in both structure and reactivity but have remained much underexplored to date. Here we report the synthesis and transformation of a new family of half‐sandwich dialkynyl complexes bearing the C5Me4SiMe3 ligand, which exhibited diverse structural features depending on metal ion size, alkyne substituent and with or without THF coordination. The acid‐base reactions between half‐sandwich rare earth dialkyl complexes (C5Me4SiMe3)Ln(CH2SiMe3)2(THF) (Ln=Sc, Y, Lu) and two equivalents of terminal alkynes such as phenylacetylene and trimethylsilylacetylene in THF generally gave the corresponding THF‐coordinated monomeric rare earth dialkynyl complexes, which upon recrystallization from toluene yielded further aggregated alkynyl complexes with partial or full dissociation of the THF ligands. In the case of phenylacetylene, trimeric yttrium and lutetium hexaalkynyl complexes were formed, in which each pair of the metal atoms was bridged by two alkynyl ligands in solid state but the alkynyl ligands underwent rapid site exchange in toluene solution. In the case of trimethylsilylacetylene with yttrium and lutetium, dimeric tetraalkynyl complexes bearing two terminal and two bridging alkynyl ligands were obtained from toluene. In contrast, recrystallization of the scandium trimethylsilylacetylide complex from toluene induced alkynyl coupling and yielded dimeric scandium complex with one butatrienediyl and two alkynyl bridging ligands. Upon dissolution in THF, all the aggregated alkynyl/butatrienediyl complexes were rapidly reconverted to the monomeric dialkynyl complexes as a result of THF coordination to the rare earth metal atoms. [ABSTRACT FROM AUTHOR]

A series of ruthenium alkenylacetylide complexes trans‐[Ru{C≡CC(=CH2)R}Cl(dppe)2] (R=Ph (1 a), cC4H3S (1 b), 4‐MeS‐C6H4 (1 c), 3,3‐dimethyl‐2,3‐dihydrobenzo[b]thiophene (DMBT) (1 d)) or trans‐[Ru{C≡C‐cC6H9}Cl(dppe)2] (1 e) were allowed to react with the corresponding propargylic alcohol HC≡CC(Me)R(OH) (R=Ph (A), cC4H3S (B), 4‐MeS‐C6H4 (C), DMBT (D) or HC≡C‐cC6H10(OH) (E) in the presence of TlBF4 and DBU to presumably give alkenylacetylide/allenylidene intermediates trans‐[Ru{C≡CC(=CH2)R}{C=C=C(Me)}(dppe)2]PF6 ([2]PF6). These complexes were not isolated but deprotonated to give the isolable bis(alkenylacetylide) complexes trans‐[Ru{C≡CC(=CH2)R}2(dppe)2] (R=Ph (3 a), cC4H3S (3 b), 4‐MeS‐C6H4 (3 c), DMBT (3 d)) and trans‐[Ru{C≡C‐cC6H9}2(dppe)2] (3 e). Analogous reactions of trans‐[Ru(CH3)2(dmpe)2], featuring the more electron‐donating 1,2‐bis(dimethylphosphino)ethane (dmpe) ancillary ligands, with the propargylic alcohols A or C and NH4PF6 in methanol allowed isolation of the intermediate mixed alkenylacetylide/allenylidene complexes trans‐[Ru{C≡CC(=CH2)R}{C=C=C(Me)}(dmpe)2]PF6 (R=Ph ([4 a]PF6), 4‐MeS‐C6H4 ([4 c]PF6). Deprotonation of [4 a]PF6 or [4 c]PF6 gave the symmetric bis(alkenylacetylide) complexes trans‐[Ru{C≡CC(=CH2)R}2(dmpe)2] (R=Ph (5 a), 4‐MeS‐C6H4 (5 c)), the first of their kind containing the dmpe ancillary ligand sphere. Attempts to isolate bis(allenylidene) complexes [Ru{C=C=C(Me)R}2(PP)2]2+ (PP=dppe, dmpe) from treatment of the bis(alkenylacetylide) species 3 or 5 with HBF4 ⋅ Et2O were ultimately unsuccessful. [ABSTRACT FROM AUTHOR]

By reaction of sodium electride or NaC 2 H with the anhydrous sodium salt of propiolic acid, Na(OOC-C≡C-H), in liquid ammonia crystalline powders of Na 2 C 3 O 2 were obtained. The structure analysis based on synchrotron powder diffraction data revealed that Na 2 C 3 O 2 crystallizes in a monoclinic unit cell (I2/a, Z=4) exhibiting the elusive Y-shaped - C≡C-COO - anion, which is unprecedented in a crystalline compound up to now. IR/Raman and solid-state NMR spectroscopic investigations with assignments supported by DFT-based ab initio calculations confirm this finding. Reaction with sodium electride led to a higher crystallinity of the product, but additionally a by-product apparently due to decomposition and polymerization of Na 2 C 3 O 2 was formed. No such by-product was observed in the reaction with NaC 2 H, which turned out to be a milder metalation route. However, the product of the latter reaction is less crystalline., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The synthesis of linear symmetric ethynyl‐ and acetylide‐amidinates of the coinage metals is presented. Starting with the desilylation of the complexes [{Me3SiC≡CC(NDipp)2}2M2] (Dipp=2,6‐diisopropylphenyl) (M=Cu, Au) it is demonstrated that this compound class is suitable to serve as a versatile metalloligand. Deprotonation with n‐butyllithium and subsequent salt metathesis reactions yield symmetric tetranuclear gold(I) acetylide complexes of the form [{(PPh3)AuC≡CC(NDipp)2}2M2] (M=Cu, Au). The corresponding Ag complex [{(PPh3)AuC≡CC(NDipp)2}2Ag2] was obtained by a different route via metal rearrangement. All compounds show bright blue or blue‐green microsecond long phosphorescence in the solid state, hence their photophysical properties were thoroughly investigated in a temperature range of 20–295 K. Emission quantum yields of up to 41 % at room temperature were determined. Furthermore, similar emissions with quantum yields of 15 % were observed for the two most brightly luminescent complexes in thf solution. [ABSTRACT FROM AUTHOR]

Reported in this contribution are the synthesis and crystal structures of new mono- and bis-phenylacetylides based on CoIII(DMC) (DMC is 5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane). Chlorido(5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane)(phenylethynyl)cobalt(III) chloride–acetonitrile–methanol (1/1/1), [Co(C8H5)Cl(C12H28N4)]Cl·CH3CN·CH3OH, 1, and (5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane)bis(phenylethynyl)cobalt(III) trifluoromethanesulfonate–dichloromethane (2/1), [Co(C8H5)2(C12H28N4)]2(CF3SO3)2·CH2Cl2, 2, were prepared under weak-base conditions in satisfactory yields. Single-crystal X-ray diffraction studies revealed that both 1 and 2 adopt a pseudo-octahedral symmetry in which the Cl—Co—C angles of 1 and C—Co—C of 2 range from 177.7 (2) to 178.0 (2)° and from 177.67 (9) to 179.67 (9)°, respectively. In both structures, the CoIII metal center is coordinated in the equatorial plane by four N atoms, in which the N—Co—N angles range from 85.6 (3) to 94.4 (3)°. The structure of 1 features two crystallographically independent molecules in its triclinic cell (Z′ = 2), which are related to each other by pseudo-monoclinic symmetry. The crystal investigated was twinned by a symmetry operator of the approximate double-volume C-centered cell (180° rotation around [201] of the actual triclinic cell), with a refined twin ratio of 0.798 (3) to 0.202 (3). Both methanol solvent molecules in 1 are disordered, the major occupancy rates refined to 0.643 (16) and 0.357 (16). Compound 2 also contains two molecules in the asymmetric unit, together with two trifluoromethanesulfonate anions [of which one is disordered; occupancy values of 0.503 (16) and 0.497 (16)] and a disordered dichloromethane [occupancy values of 0.545 (12) and 0.455 (12)].

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Abstract Described in this review is the chemistry of 3 d metal alkynyls based on tetraaza macrocyclic ligands. Both the abundance of 3 d metals and easy access to the tetraazacyclotetradecane type ligands make these compounds more affordable and sustainable alternatives to metal alkynyls based on precious metals. Taking advantage of a rich variety of starting materials available in literature, the trans- [M(cyclam)(C 2 R) 2 ]X type (cyclam = 1,4,8,11-tetraazacyclotetradecane) compounds have been prepared from the reactions between [M(cyclam)X 2 ]X (M = Cr, Fe and Co; X = Cl or OTf) and LiC 2 R. With [Co(cyclam)Cl 2 ]+, both the { trans- [Co(cyclam)Cl] 2 (μ-(C≡C) n)}2+ and trans- [Co(cyclam)(C 2 R)Cl]+ type compounds can be prepared through a dehydrohalogenation reaction. The latter type compounds can undergo a second alkynylation reaction with LiC 2 R' to afford the dissymmetric trans- [Co(cyclam)(C 2 R)(C 2 R')]+ type compounds, including the trans- [Co(cyclam)(C 2 A)(C 2 D)]+ dyads with A and D as acceptor and donor chromophores respectively. These compounds are being studied to probe photo-induced electron transfer and related photophysical/photochemical processes. The trans- [Co(cyclam)(C 2 R)(NCMe)]2+ type complexes react with unactivated HC 2 R' in the presence of a weak base to provide trans- [Co(cyclam)(C 2 R)(C 2 R')]+ in high yields. Similar alkynylation chemistry with complexes of cyclam derivatives, like TMC (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), HMC (5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) and DMC (5,12-dimethyl-1,4,8,11-tetraazacyclotetradecane), has been demonstrated with the studies of [Ni(TMC)(C 2 R)]+, trans-/cis- [Cr(HMC/DMC)(C 2 R) 2 ]+ and trans- [Co(DMC)(C 2 R) 2 ]+. Graphical abstract Image 1 Highlights • A brief overview on the history of metal alkynyl chemistry was provided. • Strategies for the synthesis of symmetric and dissymmetric M(cyclam) acetylides were analyzed. • Structure-property relationship based on spectroscopic and voltammetric studies was discussed. [ABSTRACT FROM AUTHOR]

Abstract Diastereoselective synthesis of cis -2,6-disubstituted piperidines from 1,2-cyclic sulfamidates is described. Regioselective ring-opening reactions of 1,2-cyclic sulfamidates derived from L-phenylalanine, alanine, valine, norvaline with the ketal protected acetylide with a phenyl substituent proceed smoothly to form the N -sulfamate intermediates which on acidic hydrolysis give alkynylated amines with the ketal group intact. Hydrogenation of the alkynylated amines, debenzylation, ketal deprotection, subsequent cyclization (of aminoketones) and stereoselective hydrogenation of the cyclic iminium ion intermediates afford the corresponding cis -2,6-disubstituted piperidines in high diastereoselectivity (98% ≥ d.e.) with good chemical yields (68–86%). The present approach provides a novel route for the stereoselective synthesis of cis -2,6-disubstituted piperidines. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

By reaction of alkali metal acetylides, AIC2H (AI=K, Rb, Cs), with elemental selenium in liquid ammonia highly crystalline powders of AISeC2H were obtained. The structure analysis based on the resulting synchrotron powder diffraction data revealed that all compounds crystallize in an orthorhombic unit cell (Cmc21, Z=4) exhibiting the elusive −SeC2H anion, which is unprecedented in a crystalline compound up to now. Elemental analysis and IR spectroscopic data confirm this finding. Upon heating, AISeC2H compounds release acetylene based on DSC/TGA experiments resulting in powders with the proposed composition AI2Se2(C2). The resulting powders were indexed with small cubic unit cells, but a reasonable structural model could not be developed up to now. Upon exposure of AISeC2H compounds to water elemental selenium is formed again. [ABSTRACT FROM AUTHOR]

2,1,3-Benzothiadiazole (BT) and its derivatives are very important acceptor units used in the development of photofunctional compounds and are applicable for the molecular construction of organic optoelectronic devices. Due to their strong electron-withdrawing ability, construction of molecules with the unit core of BT and its derivatives can usually improve the electronic properties of the resulting organic materials. New organometallic acetylide polymers of platinum(II) bridged by bis(fluorenyl)-benzothiadiazole moiety P1 and P2 have been synthesized via the CuI-catalyzed dehydrohalogenation reaction of the platinum(II) chloride precursors and the corresponding diacetylene ligands. The photophysical, thermal and electrochemical properties of P1 and P2 were investigated. Entry for the Table of Contents: Two new soluble platinum(II)-acetylide polymers bridged by bis(fluorenyl)-benzothiadiazole moiety are synthesized and their photophysical properties are examined. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] The reactions of α-diimine-ligated dimagnesium(I) compound [K(THF) 3 ] 2 [LMg−MgL] (1 , L = [(2,6- i Pr 2 C 6 H 3)NC(Me)] 2 2−) and terminal alkynes afford bimetallic (Mg/K) acetylide complexes (2 – 10). The reactions proceed via reductive dehydrogenation of the alkynes with release of H 2 , while the original Mg(I) center is oxidized to Mg(II). In the complexes, Mg atom is σ-coordinated either by one (2 and 3), two (4 – 9) or four (10) RC C− moieties. The (solvated) K atoms, on the other hand, are π-coordinated by the C C triple bonds and form extensive interactions with the NCCN backbone and aryl rings of the ligand and alkyl substituents of the alkyne. Interestingly, the versatile bonding modes of potassium ions result in three distinct aggregates of the complexes in the solid state, the monomer (2 – 7), dimer (8 , 9), and polymer (10), where the latter two cases benefit from the "intermolecular" interactions of K+ ions with the ligands or acetylides. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three bipyridine Pt(II) indoyl complexes have been synthesized. • The crystal structures of these bipyridine Pt(II) indoyl complexes have been determined. • The emission origin for these bipyridine Pt(II) indoyl complexes is assigned to come from the 3LLCT mixing with 3MLCT excited states. • These bipyridine Pt(II) indoyl complexes display mechanoluminescence. Three bipyridine platinum(II) complexes Pt-2-Pt-4 bearing indolyl ligand(s) have been synthesized through the hydroamidation of acetylide ligand(s) of Pt-1. The structures of Pt-1-Pt-4 were determined by single crystal X-ray diffraction. The photophysical properties of these structurally related complexes Pt-1-Pt-4 have been studied. Pt-1-Pt-4 in the solid state show emission peaks at 525–570 nm, which are assigned as the mixture of 3LLCT and 3MLCT excited states. Solids Pt-1-Pt-4 exhibit mechanoluminescence, and Pt-4G can be recovered back to solids Pt-4 upon adding a few drops of diethyl ether. This study provides a new way to synthesize bipyridine platinum(II) indolyl complexes using intramolecular hydroamidation of alkynyl moieties. [ABSTRACT FROM AUTHOR]

Reactions of a dicopper(I) tert-butoxide complex with alkynes possessing boryl or silyl capping groups resulted in formation of unprecedented tetracopper(I) μ-acetylide/diyne complexes that were characterized by NMR and UV/Vis spectroscopy, mass spectrometry and single-crystal X-ray diffraction. These compounds possess an unusual μ 4 -η 1 :η 1 :η 1 :η 1 coordination mode for the bridging organic fragment, enforced by the rigid and dinucleating nature of the ligand utilized. Thus, the central π system remains unperturbed and accessible for subsequent reactivity and modification. This has been corroborated by addition of a fifth copper atom, giving rise to a pentacopper acetylide complex. This work may provide a new approach by which metal-metal cooperativity can be exploited in the transformation of acetylide and diyne groups to a variety of substrates, or as a starting point for the controlled synthesis of copper(I) alkyne-containing clusters., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Energy remains one of the great challenges for the world. There is a considerable interest in developing renewable energy resources and improving the technologies for energy conversion. In this context, solar energy is a source with the proven capacity to meet the increasing global energy needs. In recent years, efficient organic solar cells (OSCs) have been fabricated using organic polymers and small molecules. Metalated conjugated organic molecules have also been shown to be good alternatives to the all-organic congeners and have demonstrated good promise as solar cell materials in OSCs and dye-sensitized solar cells (DSSCs). Among these, soluble molecular/polymeric metallaynes and their acetylide-functionalized metalloporphyrins show promising results in much of these investigations with the best power conversion efficiencies of 9.06% (for single-layer OSC), 12.5% (for tandem OSC) and 13.2% (for co-sensitized DSSC) to date. This review summarizes the recent advances of this field. Various factors influencing the device performance such as the nature of metal center and organic spacer, absorption coefficient, bandgap energy, charge carrier mobility, accessibility of triplet excitons and blend film morphology of these materials will be discussed. Given the diversity of transition metals available (for example, Pt, Zn, Ru) and structural versatility of the organic components, it is anticipated that this nascent field using metalated organic materials would continue to lead to exciting prospects in the near future. [ABSTRACT FROM AUTHOR]

A new rigid core dye comprised ESB-NO 2 of chromophore moieties of acetylide (C≡C), Schiff base (C˭N) and nitro (NO 2 ) was successfully synthesized to demonstrate tail-free nematogen as emitting material for organic light-emitting diode (OLED). The relationship between liquid crystal molecular structure, phase transition temperature and electroluminescence behaviour were evaluated. The mesomorphic properties of ESB-NO 2 were identified via polarized optic microscopy (POM) which displayed nematic phase of Schlieren textures and their corresponding transition enthalpies were respectively recorded at 25.15 kJ mol −1 . The photoluminescence behaviours of ESB-NO 2 have been verified at λ em,max = 538 nm where this emission are for its π→π * transition, intramolecular charge transfer (ICT) absorptions and fluoresce characters. Having ESB-NO 2 as liquid crystalline material, OLED was constructed featuring single-layer indium tin oxide (ITO) coated substrate/ ESB-NO 2 /Au via solution-casting method. The result revealed the single layer ESB-NO 2 film displayed satisfactory electroluminescence with intense yellow emission under different direct current (DC) voltages supply. These findings indicate the practicability of designing tail-free nematogenic compounds as promising solution-processed OLED materials. [ABSTRACT FROM AUTHOR]

Benzylic alkylation of enolates and acetylides has been achieved through the use of a decarboxylative benzylation strategy. Previous research in this area is often limited by the need for extended conjugation in the electrophiles that are coupled. Herein, we report that the use of 1,1'-bis(diphenylphosphino)ferrocene (dppf) ligand allows the coupling of simple benzyl electrophiles with enolates, while the use of XPhos ligand promotes the decarboxylative couplings of propiolates. [ABSTRACT FROM AUTHOR]

A novel generalized synthetic procedure for bis(acetylide) metallates(I) of the coinage metals [K(THF) n (18-crown-6)][R-C≡C- M -C≡C-R] (M = Cu, Ag, Au) with varying substituents R (R = Fc, Ph, t Bu) was developed. The synthesis proceeded under mild conditions by deprotonation of the corresponding alkyne with K{N(SiMe 3 ) 2 }, followed by salt metathesis reactions with CuCl, AgCl or AuCl(tht) (tht = tetrahydrothiophene) in the presence of 18-crown-6. The herein obtained anionic compounds represent interesting potential building blocks for homo- and heterometallic clusters. [ABSTRACT FROM AUTHOR]

Reported in this contribution are the synthesis and crystal structures of new mono- and bis-phenyl­acetyl­ides based on CoIII(DMC) (DMC is 5,12-dimethyl-1,4,8,11-tetra­aza­cyclo­tetra­deca­ne). Chlorido­(5,12-dimethyl-1,4,8,11-tetra­aza­cyclo­tetra­deca­ne)(phenyl­ethyn­yl)cobalt(III) chloride–aceto­nitrile–methanol (1/1/1), [Co(C8H5)Cl(C12H28N4)]Cl·CH3CN·CH3OH, 1, and (5,12-dimethyl-1,4,8,11-tetra­aza­cyclo­tetra­deca­ne)bis­(phenyl­ethyn­yl)cobalt(III) tri­fluoro­methane­sulfonate–di­chloro­methane (2/1), [Co(C8H5)2(C12H28N4)]2(CF3SO3)2·CH2Cl2, 2, were prepared under weak-base conditions in satisfactory yields. Single-crystal X-ray diffraction studies revealed that both 1 and 2 adopt a pseudo-octa­hedral symmetry in which the Cl—Co—C angles of 1 and C—Co—C of 2 range from 177.7 (2) to 178.0 (2)° and from 177.67 (9) to 179.67 (9)°, respectively. In both structures, the CoIII metal center is coordinated in the equatorial plane by four N atoms, in which the N—Co—N angles range from 85.6 (3) to 94.4 (3)°. The structure of 1 features two crystallographically independent mol­ecules in its triclinic cell (Z′ = 2), which are related to each other by pseudo-monoclinic symmetry. The crystal investigated was twinned by a symmetry operator of the approximate double-volume C-centered cell (180° rotation around [201] of the actual triclinic cell), with a refined twin ratio of 0.798 (3) to 0.202 (3). Both methanol solvent mol­ecules in 1 are disordered, the major occupancy rates refined to 0.643 (16) and 0.357 (16). Compound 2 also contains two mol­ecules in the asymmetric unit, together with two tri­fluoro­methane­sulfonate anions [of which one is disordered; occupancy values of 0.503 (16) and 0.497 (16)] and a disordered di­chloro­methane [occupancy values of 0.545 (12) and 0.455 (12)]. [ABSTRACT FROM AUTHOR]

Gold(I) complexes are some of the most attractive materials for generating aggregation-induced emission (AIE), enabling the realization of novel light-emitting applications such as chemo-sensors, bio-sensors, cell imaging, and organic light-emitting diodes (OLEDs). In this study, we propose a rational design of luminescent gold complexes to achieve both high thermochemical stability and intense room temperature phosphorescence, which are desirable features in practical luminescent applications. Here, a series of gold(I) complexes with ligands of N-heterocyclic carbene (NHC) derivatives and/or acetylide were synthesized. Detailed characterization revealed that the incorporation of NHC ligands could increase the molecular thermochemical stability, as the decomposition temperature was increased to ~300 °C. We demonstrate that incorporation of both NHC and acetylide ligands enables us to generate gold(I) complexes exhibiting both high thermochemical stability and high room-temperature phosphorescence quantum yield (>40%) under ambient conditions. Furthermore, we modified the length of alkoxy chains at ligands, and succeeded in synthesizing a liquid crystalline gold(I) complex while maintaining the relatively high thermochemical stability and quantum yield.

Novel Cr(III)–acetylide–tetrathiafulvalene (TTF) type complexes, [Cr(III)Cyclam(C C-MeBMT-TTF) 2 ] n + ([ 1 ] n + , Cyclam = 1,4,8,11-tetraazacyclotetradecane, MeBMT-TTF = 5-methyl-4′,5′-bis(methylthio)tetrathiafulvalene) and [Cr(III)Cyclam(C C-MeEDO-TTF) 2 ] n + ([ 2 ] 2+ , MeEDO-TTF = 5-methyl-4′,5′-ethylenedioxytetrathiafulvalene) were synthesized. Electrochemical oxidation of the complexes afforded [ 1 ](ClO 4 ) 3 (PhCl), [ 2 ](ClO 4 ) 2 (PhCl)(H 2 O) 2 and [ 2 ][CrPhen(NCS) 4 ] 2 (PhCl) 2 (Phen = 1,10-phenanthroline), where the adjacent TTF-type ligands of neighboring complexes form a (TTF) 2 n + dimer that results in a 1D chain arrangement of [ 1 ] 3+ or [ 2 ] 2+ . For [ 1 ](ClO 4 ) 3 (PhCl), the singlet nature of a divalent TTF dimer results in a weak exchange interaction between the S = 3/2 spins of Cr 3+ . By contrast, the TTF dimers in [ 2 ](ClO 4 ) 2 (PhCl)(H 2 O) 2 and [ 2 ][CrPhen(NCS) 4 ] 2 (PhCl) 2 are monovalent and have a spin of 1/2. The strong exchange interaction between the spins of the TTF dimer and Cr 3+ results in the chain of [ 2 ] 2+ being ferrimagnetic. The weak inter chain interaction and single-ion anisotropy of the TTF dimers in [ 2 ](ClO 4 ) 2 (PhCl)(H 2 O) 2 lead to weak ferromagnetic ordering at 21 K. [ABSTRACT FROM AUTHOR]

The reactions of the acetylide trinuclear derivatives [(μ-H)M 3 (CO) 9 (CCSiMe 3 )] (M=Fe, Ru) with the thiols C 6 H 5 SH and C 6 F 5 SH were carried out. Both reactions lead to the formation of products where cleavage of M-M bonds have occurred. In the case of the iron complex, two products are obtained in the reactions with both thiols: a trinuclear complex of formula [Fe 3 (CO) 9 (CCSiMe 3 )(SR)] (R=C 6 H 5 and C 6 F 5 ) and a dinuclear compound [Fe 2 (CO) 6 (CCSiMe 3 )(SR) (R=C 6 H 5 and C 6 F 5 ) which is found as anti and sy n isomers in the case of C 6 H 5 and only as the anti isomer in the fluorinated thiol. The reaction with the ruthenium complex under the same conditions gives only decomposition products, but when the reaction with pentafluorothiophenol is carried out in the presence of trimethylamine oxide, total cleavage of M-M bonds takes place to form a mononuclear complex [Ru(CO) 3 (SC 6 F 5 ) 3 ]. Spectroscopic and structural characterization of the iron complexes is given. Two isomeric crystal structures were obtained for the trinuclear fluorinated complex. [ABSTRACT FROM AUTHOR]

Polypyridyl complexes [RuCl(η 5 -C 5 Me 5 )(N–N)] ( 1 – 4 ) [N–N 2,2′-bipyridine (bpy) ( 1 ), 4,4′-dimethyl-2,2′-bipyridine (4,4′-Me 2 bpy) ( 2 ), 1,10-phenanthroline (phen) ( 3 ) and 4,7-dimethyl-1,10-phenanthroline (4,7-Me 2 phen) ( 4 )] were prepared by reacting [RuCl 2 (η 5 -C 5 Me 5 )] 2 with Zn dust in the presence of polypyridyl ligands. Unlike the related [RuCl(η 5 -C 5 Me 5 )(L1)(L2)] + [L1, L2 = P(OR) 3 , PPh 3 ] derivatives with P-donor ligands, treatment of chloro compounds 1 – 4 with diazoalkanes Ar1Ar2CN 2 afforded polypyridyl carbene complexes [Ru(η 5 -C 5 Me 5 )( CAr1Ar2)(N–N)]BPh 4 ( 5 – 8 ) [Ar1 = Ar2 = Ph ( a ), Ar1 = Ph, Ar2 = p- tolyl ( b )]. Comparative DFT studies of the formation of metallacarbenes from aromatic diazoalkanes are reported. Phosphite complex [Ru(η 5 -C 5 Me 5 )(bpy){P(OEt) 3 }]BPh 4 ( 9 ) and acetylide derivatives [Ru(η 5 -C 5 Me 5 )(C CAr)(bpy)] ( 10, 11 ) [Ar = Ph ( 10 ), p- tolyl ( 11 )] were also obtained by substitution of the carbene in 5 – 8 . Unstable vinylidene cations [Ru(η 5 -C 5 Me 5 ){ C C(H)Ar](bpy)] + ( 12, 13 ) were formed by protonation with HBF 4 •Et 2 O of acetylide species 10, 11 . The complexes were characterized spectroscopically (IR and 1 H, 13 C, 31 P NMR) and by X-ray crystal structure determination of [Ru(η 5 -C 5 Me 5 ){ C(Ph)( p- tolyl)}(bpy)]BPh 4 ( 5b ). [ABSTRACT FROM AUTHOR]

A series of bis(alkynyl) Ru 2 ( DMBA ) 4 ( DMBA = N , N ′-dimethylbenzamidinate) compounds bearing extended, acyclic, cross-conjugated frameworks (number of acetylene units ≥ 3), namely Ru 2 ( DMBA ) 4 ( L1 Si i Pr 3 ) 2 ( 1a , see Scheme 1 for the definition of L1 and L2 ) and Ru 2 ( DMBA ) 4 ( L2 Si i Pr 3 ) 2 ( 2a ), were prepared under aerobic, weak base conditions in good yields. Compounds 1a and 2a showed moderate stability and underwent protiodesilylation aided with the addition of (n-Bu) 4 NF to the free ethynyl compounds Ru 2 ( DMBA ) 4 ( L1 H) 2 ( 1b ) and Ru 2 ( DMBA ) 4 ( L2 H) 2 ( 2b ), respectively. An X-ray structural study of 1a revealed a significant deviation from the idealized D 4h geometry in the coordination sphere of the Ru 2 core, accompanied by one of the shortest Ru-C α bonds reported thus far. Electronic absorption spectral measurements imply that compounds 1a and 1b possess a smaller HOMO-LUMO gap ( ca . 1.38 eV), while the gap of 2a and 2b ( ca . 1.40 eV) is closer to the range of typical Ru 2 ( DMBA ) 4 (C 2 R) 2 -type compounds ( ca . 1.42 eV). Cyclic voltammetry measurements indicate a subtle interplay between structural and electronic properties, dependent only on the placement of the intervening olefin across the conjugation pathway. [ABSTRACT FROM AUTHOR]

A new series of small-molecular ruthenium(II)-diynes trans -Ru(dppe) 2 (C≡CAr) 2 ( D1 − D4 ) (dppe = Ph 2 CH 2 CH 2 Ph 2 ; Ar = aromatic moiety) have been successfully designed, synthesized and characterized by photophysical, electrochemical and computational methods, and complexes D1 and D3 were crystallographically characterized. The optical and time-dependent density functional theory studies showed that the absorption ability of these complexes was significantly enhanced by incorporating the stronger electron-donor groups. The effect of different electron-donor groups in these metallo-organic complexes on the optoelectronic and photovoltaic properties was also examined. In this work, benzothiadiazole as the electron acceptor and triphenylamine and/or thiophene as the electron donor were introduced in these complexes, which were found to have optimal energy bandgaps spanning from 1.70 to 1.83 eV and broad absorption bands within 300–700 nm, rendering them good electron donor materials to blend with [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 70 BM) in the fabrication of the solution-processed bulk heterojunction (BHJ) solar cells. The best power conversion efficiency (PCE) of 0.66% was achieved, which is the highest PCE in ruthenium(II)-containing BHJ solar cells to date. [ABSTRACT FROM AUTHOR]

The new derivative 1-hexanoyl-3-(4- p -tolylethynyl-phenyl)-thiourea (APHX) was synthesised by the addition reaction between 4[4-aminophenyl] ethynyltoluene and hexanoyl isothiocyanate in acetone. The acetylide group was incorporated by using Sonogashira cross-coupling reaction allowing for the preparation of acetylide-thiourea compound. APHX was then elucidated via single crystal X-ray crystallography analysis, spectroscopic and elemental analysis by Fourier Transform Infrared (FT-IR) spectroscopy, 1 H and 13 C Nuclear Magnetic Resonance (NMR), UV–visible analysis, CHNS-elemental analysis. APHX was also evaluated theoretically via density functional theory (DFT) approach. APHX was fabricated onto glass substrate via drop-cast technique prior to act as optical thin-film and its performance as volatile organic compounds (VOCs) sensor was investigated through the difference in UV–vis profile before and after exposure towards benzene. Preliminary findings revealed that APHX showed interaction towards benzene with about 48% sensitivity. According to thermogravimetric studies, APHX showed good thermal stability, without decomposition up to ca . 190 °C. Whilst, crystal structure of APHX consists in a nearly planar acylthiourea moiety with the C O and C S bonds utilizing trans position, favoring by an intramolecular N H⋯O C hydrogen bonds. The alkyl chain is oriented 90° with respect to acylthiourea group. The phenyls group in the 1-methyl-4-(phenylethynyl)benzene moieties are mutually planar and slightly twisted with respect to the acylthiourea plane. Centrosymmetric dimers generated by intermolecular N H⋯S C and C H⋯S C hydrogen bonds forming R 2 2 (8) and R 2 1 (6) motifs are present in the crystals. The interaction between APHX with benzene has been modelled and calculated using density functional theory (DFT) via Gaussian 09 software package and the preferred sites of binding are located at the acylthiourea group. [ABSTRACT FROM AUTHOR]