Synthesis and chemosensory characterization of substituted anthracene bisimide derivatives

CHED 685

Ashley D. Carbaugh, carbaughad@washjeff.edu, Department of Chemistry, Washington & Jefferson College, 60 South Lincoln St., Washington, PA 15301, Daniel S. Tyson, daniel.s.tyson@nasa.gov, Materials and Structures Division, Ohio Aerospace Institute and NASA Glenn Research Center, 21000 Brookpark Road, MS 49-1, Cleveland, OH 44135, and Michael A. Meador, Michael.A.Meador@nasa.gov, Materials and Structures Division, NASA Glenn Research Center, 21000 Brookpark Road, M.S. 49-3, Cleveland, OH 44135.
Anthracene bisimide derivatives are an under-investigated class of fluorescent dyes mainly due to synthetic difficulties and solubility limitations. A new route to the synthesis of anthracene bisimides was recently developed that utilizes the photoenolization of o-methylbenzophenones. This new class of chromophore was characterized as having visible absorption, green fluorescence, and photostability in the presence of oxygen. A systematic series of these fluorescent derivatives has already been synthesized and characterized. This study demonstrated a correlation between the charge-transfer state and the cumulative inductive effects of the substituents. Five additional anthracene bisimide derivatives have been synthesized with the following R substituents: tert-butyl benzene (1), benzo 15-crown-5 (2), methyl 18-crown-6 (3), triphenyl amine (4), and phenyl boronic acid (5), and their chemosensory behavior has been investigated. These new fluorescent dyes were characterized via absorption and emission spectroscopy, including excited-stated kinetic, extinction coefficient, and quantum yield measurements. Anthracene bisimides 1, 3, and 5 did not show any sensing behavior. However, two bisimide derivatives, 2 and 4, showed the potential to be “on-off” sensors. Compound 2 detected metal cations, such as sodium, and compound 4 revealed the presence of nitroaromatic compounds, including 2,4-dinitrotoluene,. Interestingly, these two anthracene bisimide derivatives showed an eximer effect in non-polar solvents. Current research is underway to quantify the sensing behavior of anthracene bisimide dyes 2 and 4.