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http://hdl.handle.net/2142/84215 Moore, Jeffrey S. Ray, Christian R. 2015-09-25T22:13:31Z 2015-09-25T22:13:31Z 10000-01-01 2005 2005 The synthesis of m-phenylene ethynylene (mPE) oligomers is currently a tedious process. To address this, two methods for the solid-phase synthesis of mPE oligomers (including heterosequences) have been developed. The first strategy employs a silyl-acetylene linker attached to ArgoGel(TM) solid support, and uses palladium-catalyzed cross-coupling reactions to form the desired mPE backbone in a monomer-by-monomer fashion. In order to rapidly access hexameric oligomers in a period of one to two days, efforts were taken to limit the need for deprotection steps and ensure cross-coupling conditions were complete within two hours. This led to the ability to produce mPE heterosequence hexamers with aryl bromide and terminal acetylene endgroups in good yields (typically 55-75%), in twelve hours. To increase the diversity of mPE oligomer endgroups available from solid-phase methods, a new strategy based on a triazene linker and Merrifield resin was also investigated. In this approach the mPE backbone was constructed in the same fashion as used in the silyl-acetylene linker approach. However, due to differences in resin swelling, some modification of reaction conditions were required. These new conditions allowed mPE heterosequences with aryl iodide and TMS-acetylene endgroups to be produced in 45-65% yields in forty-eight hours. Both solid-phase methods were able to produce oligomers of up to nine or ten repeat units. A method for obtaining longer-length oligomers was, however, necessary. To achieve this, a method of on-resin fragment coupling was investigated. This strategy employed previously established synthetic conditions to couple oligomer fragments onto a solid support through a silyl-acetylene linker. The on-resin mPE fragments were then subjected to a sequence of deprotection and coupling steps in order to access the desired length mPE oligomers in low, but acceptable yields. Aggregation of resin-bound oligomers may be attributed to the lack of conversion observed for the room temperature on-resin fragment coupling. Disruption of on-resin aggregates was achieved by elevating the temperature of coupling reactions. Made available in DSpace on 2015-09-25T22:13:31Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 3202158.pdf: 4664435 bytes, checksum: a67250909750a96b662ee6e4993f400b (MD5) Previous issue date: 2005 Embargo set by: Seth Robbins for item 85496 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 158 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2005. (MiAaPQ)AAI3202158 eng Chemistry, Polymer Solid Phase Synthesis of M-Phenylene Ethynylene Oligomer Heterosequences text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.