ORGN 131 |
| Polymer supports have been extensively used in many synthetic methodologies over the last 50 years. More specifically, polymer-based catalysts have been shown to facilitate catalyst and substrate recovery. In this paper, we describe the synthesis, characterization, and applications of a modified Grubbs-Hoveyda metathesis catalyst that is covalently linked to a non-polar polyisobutylene (PIB) chain. Ruthenium metathesis catalysts have been immobilized on many insoluble supports and on water-soluble or fluorous-phase soluble polymers while retaining their catalytic activity. Our system is the first example of a soluble non-polar polymeric support. Such a support allows us to use biphasic liquid-liquid separation of the product and the catalyst. Reactions both with stoichiometric amounts of the polymer relative to Ru and in the presence of an excess of a polymer ligand allow use to regenerate and to recover the catalyst as a heptane solution. Examples will be described showing how this PIB-based catalyst can be used both in ring-closing metathesis (RCM) and ring-opening metathesis polymerization (ROMP) reactions. |
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Process R&D, Physical Organic Chemistry, Heterocycles, Aromatics, Metal-Mediated Reactions
8:00 PM-10:00 PM, Sunday, March 25, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Organic Chemistry |