[7]Helicene-like compounds with a fluorene unit were successfully synthesized using a platinum-catalyzed double cyclization reaction. Crystal structures and photophysical properties of these compounds were also studied. In particular, they were found to exhibit a high fluorescence quantum yield and a relatively large g value (dissymmetric factor) of circularly polarized luminescence (CPL) for small molecules.

Fluorinated analogs of polyhedral hydrocarbons have been predicted to localize an electron within their cages upon reduction. Here, we report the synthesis and characterization of perfluorocubane, a stable polyhedral fluorocarbon. The key to the successful synthesis was the efficient introduction of multiple fluorine atoms to cubane by liquid-phase reaction with fluorine gas. The solid-state structure of perfluorocubane was confirmed using x-ray crystallography, and its electron-accepting character was corroborated electrochemically and spectroscopically. The radical anion of perfluorocubane was examined by matrix-isolation electron spin resonance spectroscopy, which revealed that the unpaired electron accepted by perfluorocubane is located predominantly inside the cage.

Unprecedented direct acceptorless dehydrogenation of C-C single bonds adjacent to functional groups to form α,β-unsaturated compounds has been accomplished by using a new class of group 9 metal complexes. Metal-ligand cooperation operated by the hydroxycyclopentadienyl ligand was proposed to play a major role in the catalytic transformation.

An efficient and practical method for the enantioselective β-functionalization of α,β-unsaturated 2-acyl imidazoles is described. The method uses a previously devised chiral-at-metal rhodium catalyst (Λ-RhS, 4 mol %) along with Hantzsch ester derivatives as alkyl radical sources. The rhodium complex exerts a dual role as the visible-light-absorbing unit upon substrate binding and as the asymmetric catalyst. The method provides up to quantitative yields with excellent enantioselectivities up to 98% ee and can be classified as a redox-neutral, electron-transfer-catalyzed reaction.

Two types of ruthenocenes and a ferrocene coordinated by rac-9H-cyclopenta[1,2-c:4,3-c']diphenanthrenyl anion(s), a [7]helicene with a cyclopentadienyl moiety at the center of its skeleton, were successfully synthesized: mono-helicene ruthenocene 1 and its iron analogue 1 with one [7]helicene ligand bound to the central metal, and bis-helicene ruthenocene 2 with two [7]helicenes. Starting from a racemic mixture of the ligand precursor, rac-2 and meso-2 were obtained in a 7:3 ratio. Since the [7]helicene has a high racemization barrier, enantiomers of the complexes were isolated in their pure forms; they showed large optical rotations and intense circular dichroism (CD) responses.