Entropically driven binding in a self-assembling molecular capsule.

J Kang; J Rebek

doi:10.1038/382239a0

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PubMed · 8717037

Entropically driven binding in a self-assembling molecular capsule.

J Kang·J Rebek

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Abstract

The encapsulation of molecules within larger molecular or supramolecular cages (see ref. 1 for examples) brings about many interesting phenomena, among them the stabilization of reactive intermediates, new forms of stereoisomerism, and templating of the cage itself. Here we describe a self-assembling hydrogen-bonded molecular capsule that encapsulates guest molecules in a reversible, apparently entropy-driven process, giving rise to unusual temperature dependence of the formation process. The positive entropy of formation--at first sight unexpected--seems to be the result of the fact that more than one solvent molecule is included in the 'bare' cage, making their replacement by a single large molecule (here adamantane or ferrocene) entropically favourable.

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Adamantane Chemical Phenomena Chemistry, Physical Dimerization Entropy Ferrous Compounds Hydrogen Bonding Magnetic Resonance Spectroscopy Metallocenes Solutions Temperature Journal Article Research Support, U.S. Gov't, P.H.S.

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J Kang, J Rebek. 1996-07-18. Entropically driven binding in a self-assembling molecular capsule.. https://doi.org/10.1038/382239a0

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