Social isomers of picolines in a small space.
Encapsulation complexes permit the observation of molecules under conditions of limited motion. Inside capsules, molecular encounters are prolonged, prearranged, and protected from the medium, in contrast to the short-lived and random encounters that occur in bulk solution. Herein, the interaction of α-, β-, and γ-picolines in a cylindrical capsule is described. Two picolines were taken up, and NMR spectra indicated dynamic combinations of various social isomers. The stabilities of the complexes are interpreted through computational methods. The shape of the space in the capsule allowed the alignment of molecules and revealed delicate, atom-to-atom interactions and attractive forces that elude observation in dilute solution. These weak forces were amplified in the isolated small space of the capsule.
The Skaggs Institute for Chemical Biology and Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, Fax: (858) 784-2876.
Dariush
D
Ajami
Giannoula
G
Theodorakopoulos
Ioannis D
ID
Petsalakis
Julius
J
Rebek
D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010847:Picolines / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry*
D010847:Picolines; D012996:Solutions
density functional calculations; encapsulation; host-guest systems; intermolecular forces; social isomerism