Polycyclic Aromatic Hydrocarbon Solute Probes. Part VII: Evaluation of Additional Coronene Derivatives as Possible Solvent Polarity Probe Molecules

Abstract

Fluorescence emission spectra are reported for dinaphtho[8,1,2abc; 2′,1′,8′klm]coronene, naphtho[8,1,2abc]coronene, naphth[2′,1′,8′,7′: 4,10,5]anthra[1,9,8abcd]coronene, dibenzo[bc,ef]coronene, benzo[1,2,3bc;4,5,6b′c′]dicoronene, anthra[2,3a]coronene, dinaphtho-[8,1,2abc;2′,1′,8′jkl]Coronene, and tetrabenzo[de,hi,mn,qr]naphthacene dissolved in n-hexadecane, butyl acetate, dichloromethane, and acetonitrile. Results of these measurements are used to screen PAHs for potential solvent polarity probe behavior. Of the eight PAHs studied, only naphtho[8,1,2abc]coronene, dinaphtho[8,1,2abc;2′,1′,8′klm]-coronene, and anthra[2,3a]coronene were classified as probe molecules. The fluorescence spectra of the first two PAHs show selective enhancement of the I band emission intensity in polar solvents. For anthra-[2,3a]coronene, the measured ratio of emission intensities of bands I and II decreased systematically with increasing solvent polarity.