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Hydrogen bond-directed aggregation of diazadibenzoperylene dyes in low-polarity solvents and the solid state.

ABSTRACT: The formation of complex superstructures via hydrogen bonding of two ditopic building blocks, diazadibenzoperylenes 1a,b and isophthalic acid 2, has been investigated. It was found that only the phenoxy-substituted diazadibenzoperylene 1a forms extended assemblies with 2 in complexes of a 1:1 stoichiometry, whereas for the 4-tert-butylphenoxy-substituted analogue 1b, no indications for superstructure formation with 2 were found. The different behavior is explained by the presence of additional pi-pi interactions, which are only observed for [1a x 2], as revealed by concentration-dependent optical absorption and fluorescence spectroscopy. Based on variable temperature x-ray diffraction studies, a lamellar structure for [1a x 2] is proposed that takes into account the concept of microphase-segregation.

SUBMITTER: Sautter A

PROVIDER: S-EPMC122709 | biostudies-literature | 2002 Apr

REPOSITORIES: biostudies-literature

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Hydrogen bond-directed aggregation of diazadibenzoperylene dyes in low-polarity solvents and the solid state.

Sautter Armin A Thalacker Christoph C Heise Bernd B Wurthner Frank F

Proceedings of the National Academy of Sciences of the United States of America 20020401 8

The formation of complex superstructures via hydrogen bonding of two ditopic building blocks, diazadibenzoperylenes 1a,b and isophthalic acid 2, has been investigated. It was found that only the phenoxy-substituted diazadibenzoperylene 1a forms extended assemblies with 2 in complexes of a 1:1 stoichiometry, whereas for the 4-tert-butylphenoxy-substituted analogue 1b, no indications for superstructure formation with 2 were found. The different behavior is explained by the presence of additional p ...[more]

PMID: 11959950

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