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Preparation, structures and preliminary host-guest studies of fluorinated syn-bis-quinoxaline molecular tweezers.

ABSTRACT: A series of polycyclic frameworks with fluorinated syn-facial quinoxaline sidewalls has been prepared as potential molecular tweezers for electron-rich guest compounds. Our synthetic route to the cyclooctadiene-derived scaffolds 16a-d takes advantage of the facile isolation of a novel spirocyclic precursor 9b with the crucial syn-orientation of its two alkene moieties. The crystal structure of 16c displays two features typical of a molecular tweezer: inclusion of a solvent molecule in the molecular cleft and self-association of the self-complementary scaffolds. Furthermore, host-guest NMR studies of compound 16c in solution show chemical exchange between the unbound and bound electron-rich guest, N,N,N',N'-tetramethyl-p-phenylenediamine.

SUBMITTER: Etzkorn M

PROVIDER: S-EPMC2874330 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Preparation, structures and preliminary host-guest studies of fluorinated syn-bis-quinoxaline molecular tweezers.

Etzkorn Markus M Timmerman Jacob C JC Brooker Matthew D MD Yu Xin X Gerken Michael M

Beilstein journal of organic chemistry 20100420

A series of polycyclic frameworks with fluorinated syn-facial quinoxaline sidewalls has been prepared as potential molecular tweezers for electron-rich guest compounds. Our synthetic route to the cyclooctadiene-derived scaffolds 16a-d takes advantage of the facile isolation of a novel spirocyclic precursor 9b with the crucial syn-orientation of its two alkene moieties. The crystal structure of 16c displays two features typical of a molecular tweezer: inclusion of a solvent molecule in the molecu ...[more]

PMID: 20502656

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