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Novel Discotic Boroxines: Synthesis and Mesomorphic Properties.

ABSTRACT: A new synthetic approach to highly substituted triphenylboroxines 11 is described. Their mesomorphic properties were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (SAXS, WAXS). The tris(3,4,5-trialkyloxy)phenyl functionalized derivatives 11b-e showed broad mesophases for a minimum alkyl chain length of C9. The phase widths ranged from 110 K to 77 K near room temperature, thus decreasing with enhanced alkyl chain lengths. Textures observed under POM indicated a columnar hexagonal (Col_h) mesophase symmetry that was confirmed by X-ray diffraction experiments.

SUBMITTER: Wohrle T

PROVIDER: S-EPMC5453236 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Novel Discotic Boroxines: Synthesis and Mesomorphic Properties.

Wöhrle Tobias T Baro Angelika A Laschat Sabine S

Materials (Basel, Switzerland) 20140522 5

A new synthetic approach to highly substituted triphenylboroxines 11 is described. Their mesomorphic properties were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (SAXS, WAXS). The tris(3,4,5-trialkyloxy)phenyl functionalized derivatives 11b-e showed broad mesophases for a minimum alkyl chain length of C9. The phase widths ranged from 110 K to 77 K near room temperature, thus decreasing with enhanced alkyl ...[more]

PMID: 28788664

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