Solvent Polarity Probe Research Articles

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

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.

Sextettumlagerungen als Solvens‐Polaritätssonde

Sextett Rearrangements as Solvent Polarity Probes The rate constant of the Chapman variant of the Beckmann rearrangement is used as a solvent polarity probe and is mainly influenced by the polarizability of the solvent. Analogies to SN reaction are discussed.