Heterogeneous self-supported organometallic nanocatalysts (ONs) were synthesized by treatment of the eta6-pi-hydroquinone rhodium complex [(1,4-hydroquinone)Rh(COD)]+ with Al(Oi-Pr)3. The organometallic nanocatalysts, the size of which can be controlled by alteration of the reaction conditions, show high catalytic activities in the stereoselective polymerization of phenylacetylene to produce cis-poly(phenylacetylene). A key feature of the ON catalyst synthesis is a facile eta6 to eta4 hapticity change occurring in the quinonoid ring, which is triggered by deprotonation of the -OH groups by Al(Oi-Pr)3, with concomitant coordination of the quinone oxygen atoms to the aluminum.

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The use of organometallic pi-complexes in the coordination-directed self-assembly of polymeric structures is a new area with many potential applications. Supramolecular metal-organometallic coordination networks (MOMNs), which are described herein, consist of metal ion or metal cluster nodes connected by bifunctional "organometalloligands" that serve as spacers. The organometalloligand utilized in this work is the stable anionic complex (eta(4)-benzoquinone)Mn(CO)(3)(-) (p-QMTC), which binds through both quinone oxygen atoms to generate MOMNs having both backbone and pendant metal sites. In many cases the MOMNs are obtained as neutral and thermally stable solids, with molecular structures that depend on the geometrical and electronic requirements of the metal nodes, the solvent, and the presence of organic spacers. Redox-active quinone-based organometallic pi-complexes permit the construction of an impressive range of coordination network architectures and hold much promise for the development of functional materials.