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Relative substituent position on the strength of pi-pi stacking interactions.

ABSTRACT: It was observed that the relative position of the arene substituents have a profound influence on the strength of pi-pi stacking in the 9-benzyl substituted triptycene system. A new series of model compounds (3a-i) capable of revealing quantitatively pi-pi stacking interactions was studied. This series of compounds (3a-i) has an ortho substituted methyl group in one of the two interacting arenes and the syn/anti ratios were determined and compared to a series previously studied compounds (4a-i) that have a para methyl group on the corresponding arene. A greater than 50% increase in the strength of pi-pi stacking interactions was observed with the methyl group in the ortho position comparing to that in the para position. No difference in pi-pi stacking interactions was observed when the other aromatic ring was a pentafluorobenzoate group.

SUBMITTER: Gung BW

PROVIDER: S-EPMC2830662 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Relative substituent position on the strength of pi-pi stacking interactions.

Gung Benjamin W BW Emenike Bright U BU Alverez Celeste N CN Rakovan John J Kirschbaum Kristin K Jain Nirbhay N

Tetrahedron letters 20100301 13

It was observed that the relative position of the arene substituents have a profound influence on the strength of pi-pi stacking in the 9-benzyl substituted triptycene system. A new series of model compounds (3a-i) capable of revealing quantitatively pi-pi stacking interactions was studied. This series of compounds (3a-i) has an ortho substituted methyl group in one of the two interacting arenes and the syn/anti ratios were determined and compared to a series previously studied compounds (4a-i) ...[more]

PMID: 20209117

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