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Dynamics of a supramolecular capsule assembly with pyrene.

ABSTRACT: Water-soluble octaacid cavitands (OAs) form dimeric capsules suitable for guest incorporation. Our studies reveal that the mechanism of pyrene (Py) binding involves the rapid (<1 ms) formation of the Py·OA complex followed by slower binding with the second OA. The dissociation of the capsular OA·Py·OA complex occurs with a lifetime of 2.7 s, which is 5 orders of magnitude slower than the microsecond opening/closing ("breathing") previously observed to provide access of small molecules to the encapsulated guest. These different dynamics of the capsules have a potential impact on how the chemistry of included guests could be altered.

SUBMITTER: Tang H

PROVIDER: S-EPMC3315598 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Dynamics of a supramolecular capsule assembly with pyrene.

Tang Hao H de Oliveira Carla Santos CS Sonntag Gage G Gibb Corinne L D CL Gibb Bruce C BC Bohne Cornelia C

Journal of the American Chemical Society 20120319 12

Water-soluble octaacid cavitands (OAs) form dimeric capsules suitable for guest incorporation. Our studies reveal that the mechanism of pyrene (Py) binding involves the rapid (<1 ms) formation of the Py·OA complex followed by slower binding with the second OA. The dissociation of the capsular OA·Py·OA complex occurs with a lifetime of 2.7 s, which is 5 orders of magnitude slower than the microsecond opening/closing ("breathing") previously observed to provide access of small molecules to the enc ...[more]

PMID: 22417319

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