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S Russell Seidel

Publications and source records attributed to S Russell Seidel.

6 recordsLinked to original sources

Coordination-driven self-assembly of supramolecular cages: heteroatom-containing and complementary trigonal prisms.

The self-assembly of three nanoscopic prisms of approximate size 1 x 4 nm is reported. Tetrahedral carbon, silicon, and phosphorus were used as structure-defining elements in these coordination-based cages. A carbon-based assembly completes a pair of nanoscopic complementary 3-D structures. The formation of the structures is supported by multinuclear NMR, ESI FT-ICR mass spectrometry, and elemental analysis data.

Anthracenes↗

Coordination-driven self-assembly of predesigned supramolecular triangles.

The design and self-assembly of three supramolecular triangles is described. A novel 60 degrees corner unit directs the exclusive formation of triangular assemblies that are not in detectable equilibrium with other macrocycles. The resulting triangles have sides ranging from 2.7 to 3.5 nm in length and molecular masses as high as 5396 amu. The crystal structure of one of the assemblies shows an approximately 1.4 nm cavity; the crystal packing forms open, triangular channels. The characterization of the supramolecular triangles by multinuclear NMR, elemental analysis, and electrospray mass spectrometry is also reported.

Cross-Linking Reagents↗

Solution and solid state studies of a triangle-square equilibrium: anion-induced selective crystallization in supramolecular self-assembly.

We report that an equilibrium mixture of triangular and square supramolecular species results when the flexible, ditopic donor unit, trans-bis(4-pyridyl)ethylene, is reacted with the ditopic acceptor unit, cis-(Me(3)P)(2)Pt(OTf)(2), in a one-to-one ratio. Both products are characterized in solution, by way of multinuclear NMR, and in the solid state, via X-ray crystallography. The effects of water and anions, cobalticarborane versus triflate, on the equilibrium are probed. The selective crystallization of either of the two species can be accomplished via the appropriate choice of solvents and ratio of anions present in the system. The dominant species in solution is not always consistent with the most prevalent species in the solid state.

Anions↗

Self-assembly of molecular prisms via an organometallic "clip".

[reaction: see text] Under the appropriate conditions, the combination of two tritopic pyridyl ligands with three metal-containing molecular "clips" spontaneously generates supramolecular coordination cages with trigonal prismatic frameworks.

Magnetic Resonance Spectroscopy↗

Self-assembly of nanoscopic coordination cages of D(3h) symmetry.

A family of nanoscale-sized supramolecular cage compounds with a trigonal prismatic framework was prepared by means of spontaneous self-assembly from the combination of a predesigned molecular "clip" with tritopic pyridyl subunits. As confirmed by x-ray crystallography, the smallest structure of the reported series is approximately 1 x 2 nm and possesses a nitrate anion incarcerated inside its molecular cavity. The largest structure has dimensions of approximately 1 x 4 nm.

Anions↗

High-symmetry coordination cages via self-assembly.

We provide a summary of our results in three-dimensional, coordination-driven self-assembly based on the directional-bonding methodology, in which the stoichiometric mixing of complementary building blocks, with appropriate, predefined geometries, leads to targeted, nanoscopic cages. Using this motif, we have synthesized high-symmetry ensembles resembling the Platonic solids, such as dodecahedra, and the Archimedean solids, such as truncated tetrahedra and cuboctahedra, as well as other cages, like trigonal bipyramids, adamantanoids, and trigonal prisms. The synthesis and characterization of these compounds is discussed, as is some host-guest chemistry.

Macromolecular Substances↗