Liquid crystalline benzothiophenes. Part 3: 2,4- and 2,7-disubstituted benzothiophenes

ABSTRACT

Five series of compounds based on 2,4- and 2,7-disubstituted benzothiophenes have been prepared and studied with respect to their mesomorphic properties. The molecular structure was modified by prolonging the molecular arms (varying the alkyl chain length) and orientation of the ester linkages. It was established that the transition temperatures and the type of the formed phases strictly depend on the ester orientation and only limited number of prepared compounds exhibited mesomorphic behaviour. Based on X-ray patterns, columnar phases were identified and found that they have centred crystallographic unit cell differing in the lattice parameters for homologous compounds. Although the bend angle of the studied materials is around 90° only, they exhibited formation of phases typical of the bent-shaped liquid crystals.

Graphical Abstract

KEYWORDS:

• Liquid crystals
• mesomorphic properties
• benzothiophene
• bent-shaped materials

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This project was supported by the Czech Science Foundation [Project No. 15-02843S].