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Two luminescent salts, [Au6(Triphos)4Au(CN)2](CF3SO3)5⋅5CH2Cl2⋅C6H5CH3 (1) and [Au6(Triphos)4] (PF6)6⋅2CH2Cl2⋅6C6H5CH3⋅H2O (2) where Triphos is bis(2-diphenyl-phosphinoethyl)phenylphosphine have been prepared from non-luminescent precursors. The luminescence in each salt results from aurophilic interactions between two or three gold(I) ions. Crystals of [Au6(Triphos)4Au(CN)2](CF3SO3)5⋅5CH2Cl2⋅C6H5CH3 (1) contain a box-like structure with an [Au(CN)2]− ion suspended between two gold(I) ions in the box. Crystals of [Au6(Triphos)4](PF6)6⋅2CH2Cl2⋅6C6H5CH3⋅H2O (2) contain a partial helical structure with pairs of gold(I) ions closely connected and surrounded by helical Ph2PCH2CH2PPh-units from two Triphos ligands. 

The reactions of open-cage fullerenes with various metal complexes show a remarkable range of unanticipated behaviors, which are compared to the corresponding reactions with intact fullerenes.

 

We report the ability to trap the dimer Au2(μ-dppe)2I2 (dppe is 1,2- bis(diphenylphosphino)ethane) with different separations between the three-coordinate gold ions in crystalline solvates. All of these solvates ((Au2(μ-dppe)2I2·4(CH2Cl2) (1), Au2(μ- dppe)2I2·2(CH2Cl2) (2), the polymorphs α-Au2(μ-dppe)2I2·2(HC(O)NMe2) (3) and β- Au2(μ-dppe)2I2·2(HC(O)NMe2) (4), and Au2(μ-dppe)2I2·4(CHCl3) (5)) along with polymeric {Au(μ-dppe)I}n·n(CHCl3) (6)) originated from the same reaction, only the solvent system used for crystallization differed. In the different solvates of Au2(μ-dppe)2I2, the Au···Au separation varied from 3.192(1) to 3.7866(3) Å. Computational studies undertaken to understand the flexible nature of these dimers indicated that the structural differences were primarily a result of crystal packing effects with aurophillic interactions having a minimal effect. 

Thienothiophene (TT) has received great attention in the fields of electronics and optoelectronics. Here we report a synthesis and characterization of fullerene-donor-fullerene triads linked to thieno[2,3-b]thio- phene as a donor. The photophysical and electrochemical properties of the new dumbbells were investi- gated using UV-vis spectroscopy, fluorescence spectroscopy, cyclic voltammetry, and square wave vol- tammetry. The results showed that both compounds have higher LUMO energy levels than PC61BM, indi- cating that they can be used in photovoltaic applications. Furthermore, the powder was structurally and morphologically characterized via X-ray diffraction (XRD) and scanning electron microscopy (SEM). The SEM revealed the morphological characterization of the two derivatives as globular and urchin-like supra- molecular assemblies. 

Six salts ([Au2(μ-dppe)2](BF4)2·CHCl3, [Au2(μ- dppe)2](BF4)2·1,2-Cl2C2H4, [Au2(μ-dppe)2](PF6)2·CHCl3, [Au2(μ-dppe)2](PF6)2, [Au2(μ-dppe)2](SbF6)2, and [Au2(μ- dppe)2](OTf)2·2CHCl3), (dppe is bis(diphenylphosphine)ethane) containing the dication, [Au2(μ-dppe)2]2+, have been prepared and structurally characterized by single-crystal X-ray crystallography. Unlike the three-coordinate dppe-bridged dimers, Au2X2(μ-dppe)2 (X = Br, I), which show considerable variation in the distance between the gold(I) ions over the range 3.0995(10) to 3.8479(3) Å in various solvates, the structure of the helical dication, [Au2(μ- dppe)2], in the new salts is remarkably consistent with the Au···Au separation falling in the narrow range 2.8787(9) to 2.9593(5) Å. In the solid state, the six crystals display a green luminescence both at room temperature and at 77 K, which has been assigned as phosphorescence. However, solutions of the dication are not luminescent. Salts containing the analogous dication [Au2(μ-dppp)2](PF6)2 (dppp is bis(diphenylphosphine)propane) have been prepared to determine whether the longer bridging ligand might also twist into a helical shape. These salts include [Au2(μ- dppp)2](OTf)2 (OTf is triflate) and three crystalline forms of [Au2(μ-dppp)2](PF6)2: the solvate [Au2(μ-dppp)2](PF6)2·(CHCl3) and two polymorphs of the unsolvated salt. None of these crystals are luminescent, but all contain a similar dication, [Au2(μ- dppp)2]2+, that contains two nearly parallel, linear P−Au−P groups and a long separation between the gold ions that varies from 5.3409(4) to 5.6613(6)Å. 

Treatment of an open-cage fullerene, designated as MMK-9, with (Ph 3 P) 4 Pt in toluene solution at room temperature allows a (PPh 3 ) 2 Pt unit to be incorporated into the rim of the cage so that it becomes an integral part of the carbon cage skeleton. The structure of the adduct has been determined by single crystal X-ray diffraction and reveals that the platinum atom has planar PtC 2 P 2 coordination, rather than the usual η 2 -bonding to an intact C–C double bond of the fullerene.