Preparation and Solid-State Properties of Self-Assembled Dinuclear Platinum(II) and Palladium(II) Rhomboids from Carbon and Silicon Tectons

Self-assembly reactions of hitherto unknown bis(4-pyridyl)silanes 2a,b with bis(triethylphosphine)platinum and bis(triethylphosphine)palladium bistriflates 5a,b lead to the formation of new silicon-containing rhomboids 6a−d. In addition, a similar carbon analogue 7 was prepared by reaction of bispyridyl acetal 4 and bis(triethylphosphine)platinum bistriflate (5a). Surprisingly, reaction of the bis(4-pyridyl)ketone (3) and the platinum complex 5a gave a similar rhomboid, 10, due to unexpected hydration of the ketone. The crystal structures of silicon complex 6a and its carbon analogue 7 were solved and compared to each other as well as to already known carbon-containing dinuclear rhomboids. In addition, the dinuclear bisporphyrin complex 8 was also characterized by X-ray structure analysis. Electrospray and FAB mass spectral data are reported as well, confirming the binuclear nature of the entities formed.