Construction of [(eta5-C5Me5)WS3Cu3]-based supramolecular compounds from preformed incomplete cubane-like clusters [PPh4][(eta5-C5Me5)WS3(CuX)3] (X = CN, Br)

Approaches to the assembly of (eta5-C5Me5)WS3Cu3-based supramolecular compounds from two preformed incomplete cubane-like clusters PPh4](eta5-C5Me5)WS3(CuX)3] (X = CN, 1a; X = Br, 1b) have been investigated. Treatment of 1a with LiBr/1,4-pyrazine (1,4-pyz), pyridine (py), LiCl/py, or 4,4'-bipyridine (4,4'-bipy) and treatment of 1b with 4,4'-bipy gave rise to a new set of W/Cu/S cluster-based compounds, Li((eta5-C5Me5)WS3Cu3(mu3-Br))2(mu-CN)3].C6H6]infinity (2), (eta5-C5Me5)WS3Cu3(mu-CN)2(py)]infinity (3), PPh4](eta5-C5Me5)WS3Cu3(mu3-Cl)(mu-CN)(CN)].py]infinity (4), PPh4]2(eta5-C5Me5)WS3Cu3(CN)2]2(mu-CN)2.(4,4'-bipy) (5), and (eta5-C5Me5)WS3Cu3Br(mu-Br)(4,4'-bipy)].Et2O]infinity (6). The structures of 2-6 have been characterized by elemental analysis, IR spectra, and single-crystal X-ray crystallography. Compound 2 displays a 1D ladder-shaped chain structure built of square-like (eta5-C5Me5)WS3Cu3(mu3-Br)(mu-CN)]4](mu-CN)2(2-) anions via two pairs of Cu-mu-CN-Cu bridges. Compound 3 consists of a single 3D diamond-like network in which each (eta5-C5Me5)WS3Cu3 unit, serving as a tetrahedral node, interconnects with four other nearby units through Cu-mu-CN-Cu bridges. Compound 4 contains a 1D zigzag chain array made of cubane-like (eta5-C5Me5)WS3Cu3(mu3-Cl)(mu-CN)(CN)]- anions linked by a couple of Cu-mu-CN-Cu bridges. Compound 5 contains a dimeric structure in which the two incomplete cubane-like (eta5-C5Me5)WS3(CuCN)2(mu-CN)]- anions are strongly held together via a pair of Cu-mu-CN-Cu bridges. Compound 6 contains a 2D brick-wall layer structure in which dimers of (eta5-C5Me5)WS3Cu3Br(4,4'-bipy)]2 are interconnected via four Cu-mu-Br-Cu bridges. The successful construction of (eta5-C5Me5)WS3Cu3-based supramolecular compounds 2-6 from the geometry-fixed clusters 1a and 1b may expand the scope of the rational design and construction of cluster-based supramolecular assemblies.