Synthesis and Properties of the 5,10,15-Trimesityltruxen-5-yl Radical

The synthesis of a long-lived, truxene-based radical that is highly delocalized and exhibits a narrow EPR absorption is reported. The radical is stable for multiple hours in a solution exposed to air and remains for months in the solid state under inert gas. Characterization and properties are discussed

Synthesis and Electronic Properties of Fluoreno[2,1‑<i>a</i>]fluorenedione and Fluoreno[1,2‑<i>a</i>]fluorenedione

The [2,1-<i>a</i>]- and [1,2-<i>a</i>]-isomers of fluorenofluorenedione have been synthesized via intramolecular Friedel–Crafts acylations. DFT calculations indicate that the [1,2-<i>a</i>]-isomer adopts a twisted, helical <i>C</i>₂-symmetric structure and that its protonated form is the thermodynamic product of the Friedel–Crafts acylation in hot sulfuric acid. Absorption spectroscopy and cyclic voltammetry measurements provide experimental estimations of frontier molecular orbital energy levels, which are reported and discussed