On the Spectacular Structural Isomorphism between CnHs Monoradical and Cn+sHs+3 Diradical Benzenoid Hydrocarbons: From Reactive Intermediates to Vacancy (Hole) Defects in Graphite

Algebraic Method for Solving Multiple Degenerate Eigenvalues in [r]Triangulenes

An algebraic procedure for overcoming the multiple degeneracy problem in eigenvalue (root) determination of the characteristic polynomial of 3-fold symmetrical molecular graphs is given. This leads to the tabulation of Hückel molecular orbital binding energy (E_π) and eigenvalues (roots) for [2]triangulene to [9]trianguene for the first time. Triangulenes are the smallest possible condensed benzenoid polyradicals.

Alcohol imination catalyzed by carbon nanostructures synthesized by C(sp2)-C(sp3) free radical coupling

Imines are important intermediates for synthesizing various fine chemicals, with the disadvantage of requiring the use of expensive metal-containing catalysts. We report that the dehydrogenative cross-coupling of phenylmethanol and benzylamine (or aniline) directly forms the corresponding imine with a yield of up to 98%, and water as the sole by-product, in the presence of a stoichiometric base, using carbon nanostructures as the "green" metal-free carbon catalysts with high spin concentrations, which is synthesized by C(sp2)-C(sp3) free radical coupling reactions. The catalytic mechanism is attributed to the unpaired electrons of carbon catalysts to reduce O2 to O2·-, which triggers the oxidative coupling reaction to form imines, whereas the holes in the carbon catalysts receive electrons from the amine to restore the spin states. This is supported by density functional theory calculations. This work will open up an avenue for synthesizing carbon catalysts and offer great potential for industrial applications.

Spreading out spin density in polyphenalenyl radicals

Properly-designed monoradicals built from polycondensed phenalene units can enforce flattening of spin distributions.