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Zimmerman, Steven C. Zeng, Fanwen 2015-05-13T15:37:29Z 2015-05-13T15:37:29Z 10000-01-01 1997 1997 Part I. Layered dendrimers were rapidly synthesized using an orthogonal coupling strategy. Fourth generation dendron 71 was prepared in four steps by sequential use of two AB$\sb2$ building blocks 66 and 67 under Mitsunobu esterification and Sonogashira coupling conditions. Further accelerated growth was achieved by merging the orthogonal coupling strategy with Frechet's branched-monomer approach. Thus, sixth generation dendron 81, with molecular formula $\rm C\sb{1292}H\sb{1369}IO\sb{242}$ and a molecular weight of 20897 amu, was synthesized in just three steps from the corresponding AB$\sb4$ monomers 72 and 73. In comparison to the most efficient dendrimer synthesis available, the orthogonal coupling strategy halves the number of synthetic steps needed by obviating protection-deprotection and activation chemistry. Part II. Discrete aggregates with a size in the nano-scale were formed by the hydrogen-bond mediated self-assembly of dendritic macromolecules. Several hydrogen bonding units were investigated, including anthyridine and diaminodihydropyridine moieties that are complementary (AAA-DDD), and self-complementary isophthalic acid, and 6-aminonicotinic acid subunits. Among them, dendritic tetraacids 189a-d were shown to self-assemble in a generation-dependent manner. The lower generation tetraacid 189a prefers to form a series of linear aggregates, while the higher generation tetraacids 189b-d tend to form a cyclic hexamer. The observation was supported by SEC dilution studies, VPO, and comparison with covalent models 208a-c. Made available in DSpace on 2015-05-13T15:37:29Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 9737300.PDF: 8844152 bytes, checksum: 9c5e0c6d0fc5919ba1f49e2be7d0e02c (MD5) Previous issue date: 1997 Embargo set by: Seth Robbins for item 78470 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 220 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1997. http://hdl.handle.net/2142/77259 (UMI)AAI9737300 eng Chemistry, Organic Chemistry, Polymer Part I: Rapid Synthesis of Dendrimers by an Orthogonal Coupling Strategy. Part II: Design, Synthesis, and Characterization of Hydrogen-Bond Mediated Self-Assembling Dendrimers text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.