Development of gold(i) phosphorescent tweezers for sensing applications

Abstract

The synthesis of the gold(I) alkynyl-fluorene compound 2 containing a diphosphane (dppb = 1,4-bisdiphenylphosphanebutane) has been easily afforded by the treatment of the previously synthesized [2-ethynylfluorene-Au]n polymer (1) and the...

Mono‐ and Dinuclear Gold(I) Coumarin Complexes: Luminescence Studies and Singlet Oxygen Production

“…This band corresponds to a π–π* absorption transition of the coumarin chromophore [13,14,27,28,34,35,45–48] . A second red‐shifted transition with lower intensity is observed for the gold(I) compounds 1 c and 2 that could be ascribed to different conformers/dimers on the ground state where aurophilic interactions are involved [16] or to or a charge transfer transition in which a gold atom is involved [5,49,50] . The emission spectra of the compounds show the typical fluorescence band from the π–π* of the coumarin that is centred at ca .…”

“…[13,14,27,28,34,35,[45][46][47][48] A second red-shifted transition ChemPlusChem with lower intensity is observed for the gold(I) compounds 1 c and 2 that could be ascribed to different conformers/dimers on the ground state where aurophilic interactions are involved [16] or to or a charge transfer transition in which a gold atom is involved. [5,49,50] The emission spectra of the compounds show the typical fluorescence band from the π-π* of the coumarin that is centred at ca. 450 nm, being 7 nm blue-shifted for the gold(I) complexes with respect to the emission of L [13,14,27,28,34,35,45] The emission quantum yields are in all cases between 20-25 % where there is not any relevant effect of the phosphane on the resulting emission efficiency but it is the double for gold(I) complexes in comparison with L, as previously observed in other gold(I)-coumarin derivatives.…”

“…The development of luminescent materials is a research area of great interest in the last decades due to the large variety of applications on different fields such as electronic displays, luminescent switches, OLEDs, optical devices or sensing materials among others. [1][2][3][4][5][6][7][8][9][10] The presence of metal atoms, and particularly, transition metal atoms, in the chemical structure of the designed luminophores is increasing attention due to the intrinsic characteristics that can offer metals regarding enhanced optical properties and chemical configuration with larger variety of coordination numbers that can easily be tuned changing completely the resulting emission with respect to their energy (emission wavelength), intensity (quantum yields) and lifetimes. In particular, heavy atoms are especially relevant on luminescence since they are also very well-known to favor the intersystem crossing (ISC) process from S 1 to T 1 excited states.…”

Heterometallic Au(I)–Cu(I) Clusters: Luminescence Studies and1O2Production

“…All compounds present an enhancement of phosphorescence QY in PMMA in comparison with the PS matrix, in agreement with recent studies with alkynyl gold(I) complexes supported in these matrices (Table 4). 20,75 Singlet Oxygen Production. The use of the two gold(I) complexes 1 and 2 and the six Au(I)−Cu(I) clusters as 1 O 2 photosensitizers has been tested since we wondered if the presence of such many heavy atoms in close proximity may have a direct influence on the population of the triplet excited state and the energy-transfer process to 3 O 2 .…”

“…Metallic centers with closed-shell d 10 electronic configurations have a tendency to form metallophilic (metal···metal) interactions. These interactions play an important role in the luminescent properties of the compounds, giving as a result compounds with different applications, for example, as luminescent materials with different colors such as blue green, red, or white emissions, thermally activated delayed fluorescence (TADF) systems, ,− or as sensors − among others. These applications depend not only on the metallophilic contacts but also on their ligands, where polydentate ligands play an important role in facilitating metal···metal proximity.…”