Supramolecular self-assembly of dendronized polymers

ORGN 71

Ken C. F. Leung, cfleung@chem.ucla.edu1, Paula Mendes1, Amar H. Flood, amarf@chem.ucla.edu1, Kaushik Patel, kaushik@chem.ucla.edu1, Hsian-Rong Tseng, hrtseng@mednet.ucla.edu2, and J. Fraser Stoddart, stoddart@chem.ucla.edu3. (1) California NanoSystems Institute and the Department of Chemistry and Biochemistry, The University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, CA 90095-1569, (2) Crump Institute for Molecular Imaging and Department of Molecular and Medical Pharmacology, UCLA, 700 westwood plaza, 1320 crump institute, Los Angeles, CA 90095, (3) California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, CA 90095-1569
Acid-base switchable supramolecular dendronized polyacetylenes [1a-c-H·PF6]nV2 from generation one [G1] to generation three [G3] (Scheme) were constructed using multiple self-assembly processes between dendritic dialkylammonium salts 1a-c-H·PF6 and a dibenzo[24]crown-8-containing polyacetylene 2. The formations of the supramolecular systems are acid-base switchable to either an ON state (rigid dendronized polymers) or an OFF state (flexible polymers). Thus, by controlling the superstructures of the supramolecular polymers, it is possible to induce conformational changes within the backbone of 2 with the [G1]-[G3] dendrons 1a-c-H·PF6. The supramolecular dendronized polymers, as well as their threading-dethreading properties, were characterized by gel permeation chromatography, UV absorption and 1H NMR spectroscopies, laser light scattering and atomic force microscopy. These results and their implications for device fabrication will be discussed.

 

Materials, Devices, and Switches
1:00 PM-5:00 PM, Sunday, 13 March 2005 Convention Center -- Room 9, Oral

Division of Organic Chemistry

The 229th ACS National Meeting, in San Diego, CA, March 13-17, 2005