ORGN 784 |
| The molecular construction of the Borromean Ring (BR) topology has long been a formidable synthetic challenge as they consist of three mutually interlocked, yet noncatenated rings. The complete molecular construction of the BR topology has been achieved successfully from 18 individual components under strict dynamic covalent, coordinative and supramolecular control. The dynamic construction of the BR topology is predicated on the ability to control the placement of 12 organic ligands around 6 transition metals. Stabilized by combinations of 12 π– π stacking interactions and 30 dative bonds, six tridentate and six bidentate ligands are spatially preorganized around six transition metals, such that they preferentially react and form molecular Borromean Rings in a single step in yields of greater than 95%. From a design point of view, in a bottom-up sense at least, this molecular BR topology provides a unique symmetrical, nanoscale three-dimensional scaffold into which unique features (e.g., electroactive, photoactive, and chiro-optical) can be imbedded at will. With the intention of exploiting the symmetry, size and topology of the BRs, we can alter strategically any one of the components (Box), be it the metal or the ligand, using the nearly quantitative synthetic protocol, to try and uncover functions that can emerge from such a form.
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Total Synthesis, Materials, Molecular Recognition, Process R&D, and Physical Organic Chemistry
8:00 PM-10:00 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster
Sci-Mix
Division of Organic Chemistry |
