Biphenyl Based Non-symmetrical Bent-Core Mesogens Containing a Chiral Moiety and an Olefinic End Group

Abstract

New nonsymmetrical bent-core compounds consisting of a biphenyl-3,4′-diol central unit, a chiral terminal chain and an olefinic end group at the other terminus have been synthesized and characterized to study the influence of a chiral moiety, the length of terminal alkenyl chain, and the number of aromatic rings in the rod-like wings which are substituted at the 3- and 4-position of central biphenyl core on mesophase properties of bent-core mesogens. The liquid crystalline properties of the compounds were investigated by differential scanning calorimetry, optical polarizing microscopy, and electro-optic methods. Depending on the length of the olefinic chain and the number of aromatic rings in the rod-like wings, the bent-core compounds with a chiral moiety show B₁ type mesophase, polar smectic C phase (SmCP) or nonmesomorphic behavior.

Keywords:

• Bent-core mesogens
• chiral moiety
• liquid crystals
• olefinic end group
• rod-like wings