285 research outputs found

    The Digital Transformation of Soccer Clubs and Their Business Models

    Get PDF
    Digital technologies are having a significant impact on the soccer industry, influencing the business models of soccer clubs and industry dynamics. For example, artificial intelligence and big data analytics are being used to improve talent scouting and management, while the internet of things, robotics, and virtual simulation are supporting tactics, training, and performance management. Gamification and augmented reality are also shaping key partnerships, and e-commerce is boosting revenues. Smart arenas are enhancing the consumer experience. The fast diffusion of digital technologies has increased business model complexity and has put firms in the position to assess the value of each technology for integration into their business models. This study maps how digital technologies are transforming each business model building block in the soccer industry and proposes a number of research questions for future research to enhance the current academic debate on the digital transformation of the soccer industry, and on the sports industry in general

    Influence of copper(I) halides on the reactivity of aliphatic carbodiimides

    Get PDF
    Carbodiimides are widely exploited in organic synthesis, and the reactivity of these compounds can be enhanced by the addition of copper(I) halides to the reaction medium. The mild reaction conditions provide an alternative and selective synthetic approach with respect to the utilization of Brønsted acids. The influence of copper(I) halides CuX (X = Cl, Br, I) on the electronic structure of diisopropylcarbodiimide and dicyclohexylcarbodiimide was investigated by means of DFT methods. The coordination of the considered carbodiimides occurs by one of the nitrogen atoms, with the formation of linear complexes having formula [CuX(carbodiimide)]. Besides varying the carbon-nitrogen bond lengths and orders, the interaction with Cu(I) reduces the electron density on the carbodiimides and alters the energies of the [NCN]-centred unoccupied orbitals, enhancing the reactivity towards nucleophiles. The computed Fukui functions suggest negligible interaction of Cu(I) with incoming nucleophiles, and the reactivity of carbodiimides is altered by coordination mainly because of the increased electrophilicity of the [NCN] fragments. CuX essentially behave as Lewis acids, and the nature of X influences the Cu-N bond strength, the carbodiimide→CuX donation and the energies of frontier unoccupied orbitals. CuCl is actually the most employed catalyst in combination with carbodiimides, but some of the results here provided suggest that the reactivity could be yet more enhanced by its replacement with CuI

    Intense red-emitting three-coordinated benzothiadiazole-based copper(I) complexes

    Get PDF
    2,1,3-benzothiadiazole (BTD) is a fluorophore commonly exploited as luminescent material for advanced applications, such as organic light-emitting diodes (OLEDs), dyes, solar and photovoltaic cells[1-4]. Ligands containing the benzothiadiazole heterocycle allowed the isolation of luminescent complexes applied in OLED technology[5,6]. In this communication we report the synthesis and characterization of heteroleptic three-coordinated Cu(I) complexes based on the benzothiadiazole heterocycle. Triphenylphosphine, diphenylphosphinomethane (dppm) and bis[(2-diphenylphosphino)phenyl] ether (DPEphos) were used as P-donor ligands. The derivatives were prepared starting from CuCl or by acidolysis of borohydride Cu(I) complexes. When [Cu(NCCH3)4][BF4] was used as precursor, four-coordinated derivatives characterized by one acetonitrile molecule in the coordination sphere were isolated. After being excited with light below 450 nm the complexes exhibited intense emissions in the red region, lifetimes up to 2 ms long and high quantum yields. XRD data highlighted that at solid state the tetrafluoroborate used as counterion is interacting with the metal centre through a fluorine. In the case of dppm, binuclear species were isolated. The replacement of tetrafluoroborate with perchlorate showed the non-innocent role of the counter-anion, affecting in particular the luminescence lifetimes. The wide emission bands were attributed to 3LC transitions on the basis of luminescence lifetime measurements and TD-DFT calculations

    N,N-Dimethyl-4-amino-2,1,3-benzothiadiazole: Synthesis and Luminescent Solvatochromism

    Get PDF
    N,N-Dimethyl-4-amino-2,1,3-benzothiadiazole (BTDNMe2) was synthesized from the commercially available 2,1,3-benzothiadiazole (BTD) by nitration in a sulfonitric mixture, followed by a reduction of the nitro group and subsequent methylation with iodomethane. BTDNMe2 was fully characterized by means of nuclear magnetic resonance (NMR) and infrared spectroscopy. The solutions of BTDNMe2 in common organic solvents revealed to be appreciably luminescent in the visible range. The electronic transitions related to the absorption and emission properties were associated with the HOMO–LUMO energy gap by means of electrochemical measurements and DFT calculations. Finally, BTDNMe2 was successfully used to prepare luminescent-doped poly(methyl methacrylate) samples

    Copper(I) borohydride complex with bis[(2-diphenylphosphino)phenyl] ether. Structure investigation by single-crystal X-Ray diffraction and DFT calculations

    Get PDF
    The borohydride anion is characterized by a rich coordination chemistry because of the variable denticity and the possibility of behaving as terminal or bridging ligand. The copper(I) complex Cu(k2-BH4)(DPEphos), where DPEphos is bis[(2-diphenylphosphino)phenyl] ether, was recently synthesized from CuCl using NaBH4 as borohydride source. The product crystallized from dichloromethane/ethanol (space group P1 ̅). The asymmetric unit contains two non-equivalent molecules, both exhibiting k2 coordination mode of the borohydride ligand, as suggested also by IR and 1H NMR spectra. The same Cu(I)-BH4 interaction was already observed for the related bis(triphenylphosphine) complex. The Cu-H distances are comprised between 1.67(3) and 1.75(2) Å, while the B-H distances are in the 1.07(2) – 1.20(2) Å range. The H-Cu-H angles for the two non-equivalent molecules are 62.7(12) and 66.3(10)°. DPEphos behaves as chelating ligand, with bite angles of 111.663(16) and 116.190(17)°. The Cu-P distances are between 2.2300(4) and 2.2776(5) Å. Bond lengths and angles of the first coordination sphere were compared with those obtained from DFT geometry optimizations, carried out using hybrid and range-separated functionals with variable percentage of Hartree-Fock exchange

    N,N-dimethyl-4-amino-2,1,3-benzothiadiazole: synthesis and luminescent solvatochromism

    Get PDF
    2,1,3-benzothiadiazole (BTD) derivatives were widely applied as herbicides, fungicides and antibacterial agents. The strong withdrawing ability of BTD and its fluorescent properties make it appealing also for the preparation of luminescent materials. Polymers containing the BTD fragment were successfully exploited for advances applications such as organic light-emitting diodes (OLEDs), dyes, solar and photovoltaic cells, as recently reported by B.A.D. Neto et al. [Eur. J. Org. Chem. (2013) 228]. To the best of our knowledge, a complete synthetic procedure for N,N-dimethyl-4-amino-2,1,3-benzothiadiazole (BTDNMe2) from the commercially available 2,1,3-benzothiadiazole was never reported. The only reference available dates back to 1976 and describes the thermal decomposition of the corresponding ammonium salt [N.M. Slavachevskaja et al., Pharm. Chem. J. 10 (1976) 327]. The synthetic route here proposed involves nitration of BTD in sulfonitric mixture, followed by reduction of the nitro-group and subsequent methylation with iodomethane. BTDNMe2 was isolated as dark red oil and it was fully characterized by means of nuclear magnetic resonance (NMR) and infrared spectroscopy. Solutions of BTDNMe2 in common organic solvents revealed to be appreciably luminescent in the visible range. The increase of dielectric constant caused a non-linear red shift of the absorption and emission maxima, an increase of the Stokes shift and a reduction of the photoluminescence quantum yield. The electronic transitions related to the absorption and emission properties were associated to the HOMO-LUMO energy gap by means of electrochemical measurements and DFT calculations. Finally, BTDNMe2 was successfully used for the preparation of luminescent doped polymethylmethacrylate samples with intense orange emission

    What drives the growth of start-up firms? A tool for mapping the state-of-the-art of the empirical literature

    Get PDF
    Purpose – This study aims to enrich the current theoretical debate on the growth of start-up firms by extensively investigating the ongoing empirical studies in this research stream. Moreover, this study identifies drivers whose support roles are confirmed in the literature and recommends further research opportunities. Design/methodology/approach – In this study, we analysed the results of 316 empirical studies on start-up firms and growth and also identified and categorised 66 growth drivers. We presented these drivers in three- dimensional charts: 1) the frequency of using each driver in the 316 studies, 2) the consistency of each driver as measured by the number of studies supporting its statistical significance and 3) the net effect (positive or negative) of each driver on growth. Findings – Our analysis compares extant studies on growth drivers and shows some under-explored growth factors of start-up firms. Practical implications – Both start-up managers and policymakers can benefit from this study. This study provided managers with a fine-grained tool on the main growth drivers and can guide policymakers in supporting policies for start-up firms. Originality/value – This study provides a rich, fine-grained and coherent picture of several potential growth drivers of start-up firms. Moreover, we extended our analysis to various potential drivers more than previous studies on this topic, thereby providing fruitful insights into the critical growth factors for start-up firms

    Green-emitting Zn(II) halide complexes with N,N,N',N'-tetramethyl-P-indol-1-ylphosphonic diamide as ligand

    Get PDF
    Zn(II) derivatives are of current interest for photophysical applications because they can enhance the emission of fluorescent ligands upon coordination. In addition, LMCT transitions involving the low-lying s or p empty orbitals of the metal center have been reported [1,2]. Herein we report the synthesis and characterization of tetrahedral Zn(II) complexes having general formula [ZnX2L2] (X = Cl, Br, I; L = N,N,N',N'-tetramethyl-P-indol-1-ylphosphonic diamide). The species were isolated from the reaction between the proper anhydrous ZnX2 salt and L under mild conditions. The structure of all the three derivatives was ascertained by single-crystal X-ray diffraction. The three species revealed to be appreciably luminescent in the green region upon excitation with UV-light below 300 nm, with emission bands centered between 520 and 530 nm. The high Stokes shifts and the luminescence lifetimes in the μs range suggest that triplet excited states are involved in the emission. On the other hand, the absorption bands are essentially ascribable to the π*←π transition of the indolyl fragment, as confirmed by DFT calculations

    Luminescent behavior of Zn(II) and Mn(II) halide derivatives of 4-phenyldinaphtho[2,1-d: 1′,2′-f][1,3,2]dioxaphosphepine 4-oxide and single-crystal X-ray structure determination of the ligand

    Get PDF
    The two enantiomers of chiral phosphonate 4-phenyldinaphtho[2,1-d:1′,2′-f][1,3,2]dioxaphosphepine 4-oxide, O=PPh(BINOL), were synthesized from the proper 1,1′-bi-2-naphtol (BINOL) enantiomer and characterized. The structure of the (S)-enantiomer was elucidated by means of single-crystal X-ray diffraction. The reaction with anhydrous ZnBr2 afforded complexes having the general formula [ZnBr2{O=PPh(BINOL)}2] that showed intense fluorescence centered in the near-UV region rationalized on the basis of TD-DFT calculations. The corresponding Mn(II) complexes with the general formula [MnX2{O=PPh(BINOL)}2] (X = Cl, Br) exhibited dual emission upon excitation with UV light, with the relative intensity of the bands dependent upon the choice of the halide. The highest energy transition is comparable with that of the Zn(II) complex, while the lowest energy emission falls in the red region of the spectrum and is characterized by lifetimes in the hundreds of microseconds range. Although the emission at lower energy can also be achieved by direct excitation of the metal center, the luminescence decay curves suggest that the band in the red range is possibly derived from BINOL-centered excited states populated by intersystem crossing
    • …
    corecore