Synthesis and characterization of self-assembling oligothiophene derivatives

ORGN 358

David A Stone, d-stone4@northwestern.edu, Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 and Samuel I. Stupp, s-stupp@northwestern.edu, Department of Chemistry, Department of Materials Science and Engineering, and Feinberg School of Medicine, Northwestern University, 2220 Campus Drive, Cook Hall 1127, Evanston, IL 60208.
Novel oligothiophene derivatives consisting of a conjugated core, hydrogen-bonding regions, and alkyl tails were synthesized in order to create a well-ordered, solution processable, conjugated material. Hydrogen bonds adjacent to the thiophene core were incorporated to help ensure g-g orbital overlap needed for efficient electron hopping which is necessary to achieve high conductivity and electron mobility. The molecules self-assemble to form self supporting gels at low concentrations (> 1 wt%) in aromatic and apolar solvents. AFM and TEM microscopy reveal that the gels consist of micron-long one-dimensional nanostructures. The degree of bundling amongst the nanostructures in these systems appears to be related to the packing ability of the peripheral alkyl tails. Optical spectroscopy reveals the thiophene cores form thermally reversible H-aggregates. Self-assembly into well ordered nanostructures is a promising route to solution processable organic electronic materials.
 

Heterocycles and Aromatics, Molecular Recognition and Self Assembly
8:00 PM-10:00 PM, Tuesday, April 8, 2008 Morial Convention Center -- Hall A, Poster

Division of Organic Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008