Long & Medium-Term Research: Synthesis and Characterization of Conducting Polymers Composed of Porphyrins Linked by Molecular Recognition Molecules This award is made under the Program for Long- & Medium- Term Research at Foreign Centers of Excellence, which enables U.S. researchers to work 3 to 12 months abroad at research centers of proven excellence, and to provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a 12-month visit by Dr. Charles M. Drain of The Rockefeller University with Professor Jean-Marie Lehn of Institut Louis Pasteur, Strasbourg, France. Various molecular, spontaneously self assembling systems are found in nature: hydrophobic and hydrophilic interactions put lipids into liquid crystalline membranes; hydrogen bonding and electrostatic interactions cause molecular recognition of DNA base pairs creating specific helical structures; and ionic forces arrange solid state lattices into crystals. All rely on molecular recognition between complementary components. As effective electronic conduction through a given media requires it be highly organized into a specific crystalline or molecular lattice, structures difficult to achieve in organic polymers and films, Dr. Drain proposes to use self assembling systems to create conducting polymers and films of synthetic porphyrins. He will use complementary molecular recognition moieties which are derivatives of hydrogen bonding molecules already described by Professor Lehn. Dr. Drain will synthesize and characterize three sets of porphyrins derivatized with the molecular recognition molecules resulting in mono, di, and tetra substituted meso-tetra-alkylporphyrins. The mono- substituted and the di-substituted porphyrins should form mesomorphic and crystalline phases via two different porphyrin intercalation geometries, while the tetra- substituted porphyrin should form highly organized monolayers on solid supports. Dr. Drain proposes to synthesize, characterize, and examine the physical properties of these arrays, including measurement of polymeric conductance and photovoltage both in lipid bilayers and on solid supports such as tin oxide. The award recommendation provides funds to cover international travel and a flat administrative allowance of $250 for the U.S. home institution.
