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Saddle-shaped tetraphenylenes with peripheral gallic esters displaying columnar mesophases.

ABSTRACT: Tetraphenylenes 2 with eight peripheral gallic esters were prepared in two steps from octamethoxytetraphenylene 1 in 19-72% yield. Investigation of the mesomorphic properties of 2 by DSC, POM and X-ray diffraction revealed that derivatives 2a-d with short alkoxy chain lengths (C(5)-C(8)) did not show any mesomorphic properties, whereas compounds 2e-i with C(9)-C(13) chains displayed rectangular columnar mesophases and compounds 2j-l with C(14)-C(16) chains displayed hexagonal columnar mesophases. Furthermore an anomalous odd-even effect of the clearing points of compounds 2e-l versus chain length was detected.

SUBMITTER: Wuckert E

PROVIDER: S-EPMC2813710 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Saddle-shaped tetraphenylenes with peripheral gallic esters displaying columnar mesophases.

Wuckert Eugen E Hägele Constanze C Giesselmann Frank F Baro Angelika A Laschat Sabine S

Beilstein journal of organic chemistry 20091021

Tetraphenylenes 2 with eight peripheral gallic esters were prepared in two steps from octamethoxytetraphenylene 1 in 19-72% yield. Investigation of the mesomorphic properties of 2 by DSC, POM and X-ray diffraction revealed that derivatives 2a-d with short alkoxy chain lengths (C(5)-C(8)) did not show any mesomorphic properties, whereas compounds 2e-i with C(9)-C(13) chains displayed rectangular columnar mesophases and compounds 2j-l with C(14)-C(16) chains displayed hexagonal columnar mesophases ...[more]

PMID: 20126633

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