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Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Chapter 1. Introduction to Molecular Tweezers Whitlock and Zimmerman developed a class of molecular hosts, popularly known as molecular tweezers, which sandwich aromatic guests by ii=ii interaction. Chapter 1 summarizes molecular tweezers of various kinds which have recently been synthesized. Chapter 2. Design and synthesis of "Bile Acid-Based Molecular Tweezers" Bile acids have a rigid backbone, and the array of hydroxyl groups separated by 5-7 A provides opportunities for the attachment of binding surfaces such as two extended chromophoric units.

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2001. / Abstract inserted. Includes bibliographical references.

Thesis (Ph. D.)--University of Chicago, Department of Chemistry, August 2003. / CD-ROM reproduces the entire dissertation in PDF format. Includes bibliographical references. Also available on the Internet.

Molecular recognition exploiting non-covalent interactions mediates the structure and function of many critical biological and synthetic molecules. There has thus been continuing and intense efforts in the design and synthesis of supramolecular systems with the capability of recognizing specific chemical species. Among various guest species, Prof. Sessler's group has been focused on the study of artificial anion receptors. Calix[4]pyrrole is a tetrapyrrolic macrocycle that is capable of binding anions via concerted and directional hydrogen bonding. Recently, a tetrathiafulvalene (TTF) functionalized calix[4]pyrrole (TTF-C4P) was synthesized and studied as a receptor for various guest species such as anions, electron deficient guest species, and C₆₀. This dissertation focuses on the recent discovery in supramolecular chemistry of TTF-calix[4]pyrrole derivatives. Chapter 1 provides a brief overview of the historical perspective, redox properties, and uses of TTF derivatives as functional building blocks for supramolecular assemblies, as well as previous findings involving the supramolecular chemistry of TTF-C4P. Chapter 2, as the major focus of this dissertation, describes ion mediated supramolecular and reversible electron transfer processes between TTF-C4P and bisimidazolium salts (BIQ²⁺2X⁻). We discovered that the electron transfer processes between these redox couples could be controlled reversibly by ion binding. Specifically, we found that anion binding to the TTF-C4P receptor promotes the forward ET processes. In contrast, cation complexation to the cavity of TTF-C4P causes the reverse ET processes. Such ion mediated ET processes play an essential role in biological ET systems including photosynthesis and respirations. These reversible ET processes were mapped out by spectroscopic (¹H-NMR, UV-Vis NIR titrations, and EPR analysis) and X-ray single crystallographic analyses of both the intermediate and products. Chapter 3 describes the synthesis of aromatic (thiophene and benzene) annulated TTF-calix[4]pyrroles as new and significantly improved receptors for poly-nitroexplosives. The resulting electronic modulations of the parent TTF-pyrrole structure result in significantly enhanced binding affinities for the corresponding TTF-C4Ps toward polynitro-explosives. This is reflected in a high level of positive homotropic allosterism. The degree of the cooperative effect was found to vary depending on the nature of both the receptors and guest species. The origin of the cooperative binding can be explained by conformational locking and an inductive effect of binding the first nitroaromatic guest. / text

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Copy of author's previously published article inserted. / Includes bibliographies / vi, 230 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis studies the B-cyclodextrins which are modified at the primary rim to incorporate an additional coordination or hydrophobic recognition site. The natural organic host, cyclodextrin and its chemically modified derivatives, are utilised as hosts for the inclusion of a range of guests. The study contributes to understanding the fundamental factors influencing selectivity of binding and the stability of the complexes formed when a guest is bound essentially at two recognition sites. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 1996