2020 was a chaotic, stressful year for most, but it did not stop innovative ideas and creative scientific thinking from flourishing. The Chemical and Engineering News, a trade magazine published by the American Chemical Society, posted a list of star molecules in 2020 according to its readers' poll.
Among them, large organic molecules with never-seen-before properties seem to be the crowd-pleasers, including a 2-dimensional metallo-supramolecule. It stood out among its peers due to its size. Previously, supramolecules that rely on metal cation for self-assembly usually lead to a compound less than 10 nm in diameter.
As reported in Nature Chemistry, an international collaboration reported a collection of 20 nm-wide giant 2-D molecules with 65 kDa of mass. These compounds were formed through ruthenium and iron-mediated intra- and intermolecular self-assembly. The team hoped that these supramolecules could be incorporated into single-molecule information storage devices.
A chemistry team from the University of Oxford came up with the largest aromatic ring thus far. In organic chemistry, the Hückel's rule is used to determine if a planar ring structure has aromatic properties. Benzene, a benchmark aromatic compound, has six delocalized electrons, thus following this rule (4n + 2) π- (in this case, n = 1).
The Oxford researchers constructed a giant molecule with a monstrosity of "free" electrons: a total of 162 π-electrons (n = 40). When this 12 porphyrins-formed structure is placed in a magnetic field, a ring current is observed with its direction strictly following Hückel's rule, which confirms its aromaticity.
Tying a Molecule into Different Knots (Chemistry Views)
Last but not least, Scientists from Chinese and British institutes reported a molecular strand that forms different kinds of tiny knots. The compound, under the coordination of different metal cations, can be folded into a three-twist knot, a trefoil knot, or a simple macrocycle.
Excited to find out what other miraculous molecules are created this year? Check out the top molecule list of 2020 from Chemistry and Engineering News.
Source: C&EN
