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.

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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.

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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.

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H-Pyridine-2-thione (C,H,NSH) reacts with [Cu( MeCN),] PF, in acetone to give an orange compound [Cu,(C,H,NS),],which crystallized in the monoclinic space group P2,/n, a = 12.257(2), b = 16.029(2), c = 9.581 (1) A, p = 108.859( 9)", and Z = 2. The single-crystal X-ray structure of the complex shows a distorted octahedral core of six copper atoms, with metal-metal distances ranging from 2.795(1) to 3.1 60( 1 ) A. Each copper has a trigonal geometry constituted by the two thiolate sulphur and one pyridine nitrogen atoms, as distinct from the common copper-thione sulphur coordination in other copper(i)-C,H,NSH complexes. The copper atom deviates highly from the S, N co-ordination plane. The reaction solution was examined by 'H n.m.r. spectroscopy, which reveals the formation of several low-molecular-weight species in the early stages of the reaction.The great interest in copper@ complexes stems in part from the unique and sometimes puzzling variation in their structural formats and chemical reactivity with changes in ligands, and also from the desire to understand the mode of action of the proteins having copper centres.2 The recent findings that copper(1) can form high nuclearity complexes have added an additional and intriguing dimension to this copper(1) chemistry. The size of copper cores ranges from two to t ~e l v e . ~ However, copper(1) complexes of high nuclearity are still sparse, and the number of examples sharply decreases with the increasing nuclearity.1 H-Pyridine-2-thione (C,H,NSH) co-ordinates as such through the sulphur atom in its most common modes of coordination (A) and (B), leading to the formation of mononuclear and binuclear complexes of copper(^)., Distinct from other transition-metal complexe~,~ where it can co-ordinate as the conjugate anion, pyridine-Zthionate (C5H4NS -), in various ways, the co-ordination of CSH,NS-to copper(1) is rare, indicating that copper(1) seems to prefer CSH4NSH. Although the reaction of C,H,NSH with copper-(I) or -(n) gives various species,, most have not been structurally characterized.We have found that the reaction of [Cu(MeCN),JPF, with CSH4NSH results in the formation of [Cu,(C,H,NS),], which has a discrete cluster structure consisting of C,H4NS-groups bonded to the c u 6 core by Cu-S-Cu and Cu-N bonds, (C). This paper concerns the preparation of this complex and its X-ray crystallographic structure, and the investigation of the reaction of C5H,NSH by 'H n.m.r. spectroscopy.