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Influence of spacer chain lengths and polar terminal groups on the mesomorphic properties of tethered 5-phenylpyrimidines.

ABSTRACT: Based on 5-(4-hydroxyphenyl)-2-octylpyrimidine 8, 5-phenylpyrimidine derivatives 3-7, 9 with different spacer chain lengths (C(2) up to C(6)) and different terminal polar groups (Br, Cl, N(3), OH, CN) were synthesized by etherification and nucleophilic substitution. The mesomorphic behaviour of these compounds was investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (WAXS and SAXS) and revealed smectic A mesophases for bromides, chlorides and azides 3, 4 and 6. For these compounds a maximum phase width was observed for the C(5) spacer regardless of the terminal group, whereas the hydroxy- and cyano-substituted derivatives 5 and 7, respectively, were non mesomorphic and showed only melting transitions.

SUBMITTER: Starkulla GF

PROVIDER: S-EPMC2839790 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Influence of spacer chain lengths and polar terminal groups on the mesomorphic properties of tethered 5-phenylpyrimidines.

Starkulla Gundula F GF Kapatsina Elisabeth E Baro Angelika A Giesselmann Frank F Tussetschläger Stefan S Kaller Martin M Laschat Sabine S

Beilstein journal of organic chemistry 20091109

Based on 5-(4-hydroxyphenyl)-2-octylpyrimidine 8, 5-phenylpyrimidine derivatives 3-7, 9 with different spacer chain lengths (C(2) up to C(6)) and different terminal polar groups (Br, Cl, N(3), OH, CN) were synthesized by etherification and nucleophilic substitution. The mesomorphic behaviour of these compounds was investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (WAXS and SAXS) and revealed smectic A mesophases for bromides, chlor ...[more]

PMID: 20300461

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