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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. 

Abstract We present the inaugural synthesis of a chiral teropyrene achieved through a four‐fold alkyne benzannulation catalyzed by InCl₃, resulting in good yields. The product underwent thorough characterization using FT‐Raman and FT‐IR spectroscopies, demonstrating a close agreement with calculated spectra. X‐ray crystallographic analysis unveiled a notable twist in the molecule‘s backbone, with an end‐to‐end twist angle of 51°, consistent with computational predictions. Experimentally determined enantiomeric inversion barriers revealed a significant energy barrier of 23 kcal/mol, facilitating the isolation of enantiomers for analysis by circular dichroism (CD) and circularly polarized luminescence (CPL) spectroscopies. These findings mark significant strides in the synthesis and characterization of chiral teropyrenes, offering insights into their structural and spectroscopic properties. 

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. 

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. 

The discovery of a third, non-luminescent crystalline polymorph of [(C 6 H 11 NC) 2 Au]PF 6 is reported. Remarkably, crystals of this polymorph are sensitive to mechanical pressure or to exposure to dichloromethane vapor. In both cases, the conversion produces the yellow, green luminescent polymorph of [(C 6 H 11 NC) 2 Au]PF 6 and not the colorless, blue luminescent polymorph. 

Cocrystallization of Ni II (OEP) (where OEP is the dianion of octaethylporphyrin) with C 70 in p -xylene produces black plates of 12Ni II (OEP)·12C 70 ·18 p -xylene ( 1 ). Single crystal X-ray diffraction at 90 K reveals that the crystal contains 42 individual, well-ordered molecules in the asymmetric unit with distinctive interactions between each Ni II (OEP)/C 70 pair and each pair of neighboring C 70 molecules. Warming the crystal to 186 K produces a phase change so that only four Ni II (OEP)/C 70 sites and six p -xylene molecules are present. Under the same conditions Cu II (OEP) cocrystallizes with C 70 to form Cu II (OEP)·C 70 ·1.5 p -xylene ( 2 ) with a much simpler structure consisting of one molecule of the porphyrin and the fullerene along with 1.5 molecules of p -xylene in the asymmetric unit. Crystallization of C 70 from toluene in the presence of Ni II (etioporphyrin-I) produces the black solvate 6C 70 ·6toluene ( 3 ). It seems that C 70 has a tendency to crystallize so that several orientations of the oblong molecule are present in the solid.