Four organosilver(I) complexes of polycyclic aromatic hydrocarbons (PAHs) have been investigated crystallographically. The aim was to establish whether a favorable combination of cation-π interactions and aromatic stackings might produce functional organometallic solid materials with novel networks. Complete structures of the silver(I) perchlorate with 9,10-diphenylanthracene (L1), rubrene (L2), benzo[a]pyrene (L3), and coronene (L4) were determined by X-ray diffraction. All compounds are organometallic species based on cation-π interactions. While complex 1 with L1 revealed a discrete mononuclear structure, complex 2 with rubrene displayed a π-bonded 3-D polymer. Complexes 3 and 4 can be regarded as both coordination polymer and stacking polymer, and the detailed differences in the geometries and the stacking patterns of L3 and L4 gave helical and triple-decker networks, respectively. The ESR spectroscopic results and conductivity of the compounds are also discussed. The present findings may serve as a basis for understanding specific interactions responsible for self-assembly of multinuclear aggregates involving PAHs.

A new class of metal sandwich complexes of silver derived from silver(I) perchlorate and fluoranthene (L1), benzo[ghi]perylene (L2), [2,2]paracyclophane (L3), and decacyclene (L4) was prepared. The idea behind the use of polycyclic aromatic compounds as an alternative approach for construction of organometallic sandwich systems is to combine the plasticity of the metal ion and planarity and coordinative diversity of the hydrocarbons. Structural studies by single-crystal X-ray diffraction have shown that all compounds contain extended one- to three-dimensional structures in which several metal atoms are sandwiched between two fused polycyclic systems. While complex 1, [Ag3(L1)2(ClO4)3], exists in the solid state as a two-dimensional W-type architecture in which AgClO4 layers are separated by two sheets of hydrocarbon, complex 2, [Ag(L2)(ClO4)]4·toluene, contains two double-decker polymeric chains coupled via extensive aromatic π−π stackings. Pillared brick sandwiched framework was observed in 3, [Ag(L3)(ClO4)], whereas the multidecker sandwich complex 4, [Ag2(L4)(ClO4)2(benzene)], is reminiscent of ladder. The structure of L1 has been redetermined and that of L2 reported; the structural data are used for discussion of the silver−π interactions. The electrochemical behavior and ESR spectra are consistent with formation of the organic radical species in the system. The present findings may represent an alternative approach for predesigning the multilayered systems in organometallic chemistry.

Three luminescent silver(I)-oligo(phenylenevinylene) complexes, [Ag2(bmsb)(ClO4)2] (1), [Ag2(bmsb)(H2O)4](BF4)2 (2), and [Ag2(bdb)(CF3SO3)2] (3) (bmsb = 1, 4-bis(methylstyryl)benzene, bdb = 4,4'-bis(2, 5-dimethylstryryl)biphenyl), have been synthesized and structurally characterized. Complexes 1 and 2 are 2D networks with unique metallocyclophane motifs. Complex 3 affords a 2D zigzag sheet, in which silver triflates form tubelike double chains and bdb molecules act as linkages. Complex 2 exhibits high electric conductivity because of columnar aromatic stackings formed through intra- and intermolecular pi-pi interactions. Complexes 1-3 in the solid state exhibit luminescence, of which excitation and emission maxima are shifted to longer wavelength as compared to those of the corresponding metal-free ligands.

Two organosilver(I) compounds of pylene and perylene presented here exhibit an unusual tetra-η2-coordination, bridging four metal centers and leading to W-type sandwich polymeric chains and sheets. Both compounds, show typical radical cation ESR signals upon irradiation with light or iodination.

• Prenatal diagnosis for an invasive placenta is essential for perinatal planning. • Magnetic resonance imaging provides useful information for the diagnosis of invasive placenta. • The placental protrusion sign is a useful novel MRI finding for predicting invasive placenta.

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MTV and TLG of primary endometrial cancer show better correlations with clinicopathological features and are more useful for differentiating high-risk from low-risk carcinoma than SUVmax.