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dc.contributor.authorRichardson, John Michaelen_US
dc.date.accessioned2008-06-10T20:46:57Z
dc.date.available2008-06-10T20:46:57Z
dc.date.issued2008-01-15en_US
dc.identifier.urihttp://hdl.handle.net/1853/22704
dc.description.abstractThis work focuses on understanding the heterogeneous/homogeneous nature of the catalytic species for a variety of immobilized metal precatalysts used for C-C coupling reactions. These precatalysts include: (i) tethered organometallic palladium pincer complexes, (ii) an encapsulated small molecule palladium complex in a polymer matrix, (iii) mercapto-modified mesoporous silica metalated with palladium acetate, and (iv) amino-functionalized mesoporous silicas metalated with Ni(II). As part of this investigation, the use of metal scavengers as selective poisons of homogeneous catalysis is introduced and investigated as a test for distinguishing heterogeneous from homogeneous catalysis. The premise of this test is that insoluble materials functionalized with metal binding sites can be used to selectively remove soluble metal, but will not interfere with catalysis from immobilized metal. In this way the test can definitely distinguish between surface and solution catalysis of immobilized metal precatalysts. This work investigates three different C-C coupling reactions catalyzed by the immobilized metal precatalysts mentioned above. These reactions include the Heck, Suzuki, and Kumada reactions. In all cases it is found that catalysis is solely from leached metal. Three different metal scavenging materials are presented as selective poisons that can be used to determine solution vs. surface catalysis. These selective poisons include poly(vinylpyridine), QuadrapureTM TU, and thiol-functionalized mesoporous silica. The results are contrasted against the current understanding of this field of research and subtleties of tests for distinguishing homogeneous from heterogeneous catalysis are presented and discussed.en_US
dc.publisherGeorgia Institute of Technologyen_US
dc.subjectPalladium catalysisen_US
dc.subjectCross coupling reactionen_US
dc.subjectHeterogeneous vs. homogeneousen_US
dc.subjectSelective poisoningen_US
dc.subject.lcshPalladium catalysts
dc.subject.lcshHeterogeneous catalysis
dc.subject.lcshCatalysis
dc.subject.lcshCatalyst poisoning
dc.titleDistinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisonsen_US
dc.typeDissertationen_US
dc.description.degreePh.D.en_US
dc.contributor.departmentChemical and Biomolecular Engineeringen_US
dc.description.advisorCommittee Chair: Dr. Christopher W. Jones; Committee Member: Dr. E. Kent Barefield; Committee Member: Dr. Marcus Weck; Committee Member: Dr. Pradeep Agrawal; Committee Member: Dr. Rachel Chenen_US


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