title: Amplified halogen bonding in a small space.
abstract: Weak, intermolecular forces are difficult to observe in solution because the molecular encounters are random, short-lived, and overwhelmed by the solvent. In confined spaces such as capsules and the active sites of enzymes or receptors, the encounters are prolonged, prearranged, and isolated from the medium. We report here the application of encapsulation techniques to directly observe halogen bonding. The small volume of the capsule amplifies the concentrations of both donor and acceptor, while the shape of the space permits their proper alignment. The extended lifetime of the encapsulation complex allows the weak interaction to be observed and characterized by conventional NMR methods under conditions in which the interaction would be negligible in bulk solvent.
authors.affiliation: The Skaggs Institute for Chemical Biology and Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.
authors.forename: Mohammed G
authors.initials: MG
authors.lastname: Sarwar
authors.forename: Dariush
authors.initials: D
authors.lastname: Ajami
authors.forename: Giannoula
authors.initials: G
authors.lastname: Theodorakopoulos
authors.forename: Ioannis D
authors.initials: ID
authors.lastname: Petsalakis
authors.forename: Julius
authors.initials: J
authors.lastname: Rebek
mesh_terms: D002214:Capsules; D006219:Halogens / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure
chemical_list: D002214:Capsules; D006219:Halogens