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Ring-alkyl connecting group effect on mesogenic properties of p-carborane derivatives and their hydrocarbon analogues.

ABSTRACT: The effect of the phenyl-alkyl connecting group on mesogenic properties of several series of isostructural compounds containing p-carborane (A and B), bicyclo[2.2.2]octane (C), and benzene (D) was investigated using thermal and optical methods. Results demonstrated that mesophase stability in the series containing A-D follows the order (Alk)CH?CH?- < (Alk)OOC- < (Alk)CH?O- < (Alk)COO-. Surprisingly, the connecting groups (Alk)CH?CH?- and (Alk)OOC- destabilize the mesophase significantly stronger for carboranes (A and B) than for carbocyclic derivatives (C and D). Analysis indicates that this effect may have quadrupolar and conformational origin.

SUBMITTER: Jankowiak A

PROVIDER: S-EPMC2839553 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Ring-alkyl connecting group effect on mesogenic properties of p-carborane derivatives and their hydrocarbon analogues.

Jankowiak Aleksandra A Kaszynski Piotr P Tilford William R WR Ohta Kiminori K Januszko Adam A Nagamine Takashi T Endo Yasuyuki Y

Beilstein journal of organic chemistry 20091230

The effect of the phenyl-alkyl connecting group on mesogenic properties of several series of isostructural compounds containing p-carborane (A and B), bicyclo[2.2.2]octane (C), and benzene (D) was investigated using thermal and optical methods. Results demonstrated that mesophase stability in the series containing A-D follows the order (Alk)CH₂CH₂- < (Alk)OOC- < (Alk)CH₂O- < (Alk)COO-. Surprisingly, the connecting groups (Alk)CH₂CH₂- and (Alk)OOC- destabilize the mesophase significantly stronger ...[more]

PMID: 20300457

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