Host-guest chemistry

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Crystal structure of a host-guest complex with a p-xylylenediammonium bound within a cucurbituril reported by Freeman in Acta. Crystallogr. B, 1984, 382-387.

A guest N₂ is bound within a host hydrogen-bonded capsule reported by Julius Rebek et al. in Chem. Eur. J. 1996, 2, 989-991.

In supramolecular chemistry, host-guest chemistry describes complexes that are composed of two or more molecules or ions held together in unique structural relationships by hydrogen bonding or by ion pairing or by Van der Waals force other than those of full covalent bonds.

The host component is defined as an organic molecule or ion whose binding sites converge in the complex and the guest component is defined as any molecule or ion whose binding sites diverge in the complex. Analogously, in immunology, the host is the antibody and the guest the antigen.

[edit] Host cavities or cavitands

• Cyclodextrins
• Calixarenes
• Cucurbiturils
• Porphyrins
• Crown ethers

[edit] Examples

Host-guest chemistry is observed in:

• Inclusion compounds
• intercalation compounds
• Clathrates
• Cryptands
• Molecular tweezers

[edit] See also

• Molecular recognition
• Supermolecule