Cavities promote reactions, and they can also trap the products of reactions. Such (supramolecular) chemistry is used to provide models for how enzymes work, but it also allows un-natural reactions to be undertaken. A famous example is the preparation of P4 (see blog post here), an otherwise highly reactive species which, when trapped in the cavity is now sufficiently protected from the ravages of oxygen for its X-ray structure to be determined. A colleague recently alerted me to a just-published article by Legrand, van der Lee and Barboiu (DOI: 10.1126/science.1188002) who report the use of cavities to trap and stabilize the notoriously (self)reactive 1,3-dimethylcyclobutadiene (3/4 in the scheme below). Again sequestration by the host allowed an x-ray determination of the captured species!
Posts Tagged ‘supramolecular’
Tags:author, Barboiu, catalysis, cavity, crystalline calixarene network, cyclobutadiene, Diels Alder, free energy, free energy barrier, gas phase calculation, host/guest, Interesting chemistry, Legrand, pericyclic, Prins, supramolecular, van der Lee, watoc11, X-ray
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