IRFP: Boron-Containing Organic Donor-Acceptor Scaffolds: Chemoresponsive Optoelectronic Materials

Finke Aaron D, Urbana IL

Investigators

Abstract

The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four-month research fellowship by Dr. Aaron D. Finke to work with Dr. Francois Diederich at the ETH-Zurich in Zurich, Switzerland. The proposed research concerns the effects of boron incorporation in a novel class of organic chromophores. [2+2] cycloaddition/cycloreversion chemistry with electron-rich alkynes and electron-poor olefins is an ideal method for preparation of chromophores of small size because of its synthetic facility, atom economy, and generation of complexity. These chromophores, which contain an electron-rich aniline and electron-poor tetracyanobutadiene, are typically highly-colored due to strong charge-transfer behavior, and exhibit reduction potentials on par with the best organic electron-acceptors currently known. They also possess high nonlinear optical activity which has been exploited in devices such as optical waveguides. Studies on the incorporation and effects of different functional groups to modulate the optoelectronic properties of these chromophores have been limited. The addition of electron-accepting boron moieties into conjugated organic systems should allow for stronger electron-accepting properties as well as introduce a new ability to more finely "tune" the electron-accepting behavior, and thus the optical and electrochemical properties, of these materials. Once a greater understanding of organoboron-containing "super-acceptors" is gained, the proposed research will seek to exploit the chemoresponsive nature of organoboron-containing functional groups for novel chemical sensing applications. This work will enhance our understanding of the effects of electron-accepting groups in strong organic acceptor materials. Main-group element incorporation into conjugated organic materials will futher diversify the types of organic electronic materials that are currently available. Boron's high availability, low cost, and low toxicity make it attractive for the development of "greener" materials for devices that currently rely on expensive and/or toxic metals. Furthermore, the incorporation of chemically-responsive moieties such as organoboranes into conjugated systems should allow for new approaches toward systems for the detection of environmental contaminants such as fluoride for public health applications.