The synthesis and investigation of the electronic properties of crown ether, [2]-catenane, and [2]-rotaxane architectures

Scope. The body of work described in this thesis focuses on the synthesis of donor-acceptor architectures of the pseudorotaxane, rotaxane, and catenane genres. The binding constants of thiophene and phenylene-ethynylene based crown ethers are determined via fluorescence quenching titrations, in an attempt to correlate structure with binding affinities. The insight obtained from the binding constant determinations allows for the proper choice of crown ether for the formation of [2]-catenanes and [2]-rotaxanes. The electronic properties of these complexes are then probed by electrochemical, spectroelectrochemical, and conductivity measurements. The potential of a poly([2]-catenane) as a photoconductive polymer is also investigated. The obstacles encountered in synthesizing poly([2]-rotaxanes) is also discussed, with emphasis on end-group strategies that aid in thwarting electrochemically induced dethreading. Chapter 1. This chapter provides a broad overview of the physical methods utilized in this thesis. Electrochemical methods are covered, with particular emphasis on oxidative polymerization of heteroaromatic monomers. Correlation between electrode phenomena and cyclic voltammogram waveshapes is included, in order to reinforce an understanding of the various electrochemical processes. Electroactive catenane and rotaxane supramolecules feature prominent in the literature, and a brief overview of significant examples is given. Advanced electrochemical techniques regarding in-situ conductivity measurements and spectroelectrochemistry are discussed. The elucidation of binding affinities for hosts and guest via fluorescence spectroscopy, a major theme in Chapter 2, is presented with focus on interpreting Stern-Volmer plots.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2002

Author dc:creator

• Simone, Davide Louis, 1973-

Advisor dc:contributor.advisor

• Timothy M. Swager.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/8365

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/8365