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Volume 12 Issue 3, March 2020

Volume 12 Issue 3

Bigging up aromaticity

Benzene is the archetypal aromatic molecule and it satisfies Hückel's 4n + 2 rule with its 6 π-electrons (n = 1). In a study that explores the limits of aromaticity, Harry Anderson and co-workers have now shown that Hückel's rule holds true for a large wheel-like compound in which 12 zinc porphyrins are linked together with diyne groups. In the 6+ oxidation state, the 162 π-electrons (n = 40) are delocalized around the porphyrin wheel, which is shown on the cover with two template molecules stacked inside it to form a stable 2:1 complex.

See Rickhaus et al

IMAGE: Harry Anderson, University of Oxford. COVER DESIGN: Tulsi Voralia

News & Views

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Perspectives

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Articles

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    The mechanochemical activation of [4]-ladderane/ene has been studied and found to exhibit cascade unzipping and a consistent stereochemical distribution of products under various conditions and in different polymer backbones. Ab initio steered molecular dynamics simulations revealed unique non-equilibrium dynamic effects in the mechanochemistry of ladderane, cascade activation and reaction pathway bifurcation.

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