eprintid: 6307 rev_number: 4 userid: 6 dir: disk0/00/00/63/07 datestamp: 2011-11-10 19:31:10 lastmod: 2016-11-15 13:36:11 status_changed: 2011-11-10 19:31:10 type: thesis_degree metadata_visibility: show contact_email: jdunn@colorado.edu item_issues_count: 0 eprint_status: archive creators_name: McCabe, Jamie Marie creators_email: jdunn@colorado.edu title: APPLICATIONS OF Rh(I)-CATALYSIS TO NATURAL PRODUCT SYNTHESIS: ROUTES TO OVALICIN AND GUANACASTEPENE A ispublished: unpub divisions: sch_as_chemistry full_text_status: public keywords: Allenic Alder-ene; cyclocarbonylation; Rhodium abstract: Transition metal-catalyzed carbon-carbon bond formation is an efficient method to rapidly increase molecular complexity via skeletal reorganization and/or cycloaddition processes. The mild conditions, functional group compatibility, and high regio- and stereoselectivities of these transition metal-catalyzed reactions are just a few reasons for their prominence in natural product synthesis. The first section describes a route to ovalicin via an allenic Alder-ene reaction using Rh(I)-catalysis. The scope of the novel allenic Alder-ene reaction using Rh(I) and Ir(I) catalysts has been extended to differentially substituted 1,1,3-trisubstituted allenes. The allenyl substitution pattern can give three possible cross-conjugated triene products. The selectivity of this transformation can be controlled by varying reaction temperature, solvent, catalyst and functional groups. Progress towards the synthesis of ovalicin using this triene forming protocol is described. The second section describes a route to guanacastepene A via a Rh(I)-catalyzed allenic cyclocarbonylation reaction. Efficient synthetic reactions, readily available and inexpensive starting materials and practical and convenient conditions all contribute to the success of a synthesis of the carbocyclic core of guanacastepene A and are the primary focus of the first half on this chapter. Upon the highly efficient formation of the carbocyclic core to guanacastepene A, our attention turned to the installation of an angular methyl group at C13. The routes evaluated to effect this transformation were a 1,4-conjugate addition, a reductive ring opening of a cyclopropyl ketone, and a radical cyclization of a bromo-silane moiety. date: 2007-06-22 date_type: completed institution: University of Pittsburgh refereed: TRUE etdcommittee_type: committee_chair etdcommittee_type: committee_member etdcommittee_type: committee_member etdcommittee_type: committee_member etdcommittee_name: Brummond, Kay M. etdcommittee_name: Curran, Dennis P. etdcommittee_name: Lazo, John S. etdcommittee_name: Floreancig, Paul E. etdcommittee_email: kbrummon@pitt.edu etdcommittee_email: curran@pitt.edu etdcommittee_email: florean@pitt.edu etdcommittee_id: KBRUMMON etdcommittee_id: CURRAN etdcommittee_id: FLOREAN etd_defense_date: 2007-02-28 etd_approval_date: 2007-06-22 etd_submission_date: 2007-01-26 etd_access_restriction: immediate etd_patent_pending: FALSE assigned_doi: doi:10.5195/pitt.etd.2011.6307 thesis_type: dissertation degree: PhD committee: Kay M. Brummond (kbrummon@pitt.edu) - Committee Chair committee: Dennis P. Curran (curran@pitt.edu) - Committee Member committee: John S. Lazo () - Committee Member committee: Paul E. Floreancig (florean@pitt.edu) - Committee Member etdurn: etd-01262007-125349 other_id: http://etd.library.pitt.edu/ETD/available/etd-01262007-125349/ other_id: etd-01262007-125349 citation: McCabe, Jamie Marie (2007) APPLICATIONS OF Rh(I)-CATALYSIS TO NATURAL PRODUCT SYNTHESIS: ROUTES TO OVALICIN AND GUANACASTEPENE A. Doctoral Dissertation, University of Pittsburgh. (Unpublished) document_url: http://d-scholarship-dev.library.pitt.edu/6307/1/jmmccabeapril2007.pdf