170286-41-6

Upstream product

• 3575-31-3 4-octylbenzoic acid 
• 123-08-0 4-hydroxy-benzaldehyde 
• 62808-20-2 4-(4-octylbenzoyloxy)benzaldehyde 
• 50606-97-8 p-n-octylbenzoyl chloride 

Downstream Products

• 1291073-94-3 C₅₁H₅₃NO₈ 

Relevant academic research and scientific papers

Controlling the formation of heliconical smectic phases by molecular design of achiral bent-core molecules

Fluids with spontaneous helical structures formed by achiral low molecular mass molecules is a newly emerging field with great application potential. Here, we explore the chemical mechanisms of the helix formation by systematically modifying the structure of a bent 4-cyanoresorcinol unit functionalized with two different phenyl benzoate based aromatic rods and terminated with two alkyl chains of variable length. The majority of these achiral compounds self-assemble, forming a short-pitch heliconical liquid crystalline phase in broad temperature ranges. In some cases, it occurs without any competing low-temperature phase. We demonstrate that the mirror symmetry broken mesophase occurs at the paraelectric-(anti)ferroelectric transition if the tilt angle of the molecules in the smectic layers is around 18-20° and if this transition coincides with a change of the tilt correlation between the layers. In the close vicinity of this transition, a field-induced heliconical phase develops as well as a new heliconical phase with polarization-randomized structure. These investigations provide a blueprint for the future design of achiral molecules capable of spontaneous mirror symmetry breaking by the formation of heliconical liquid crystalline phases.

Nematic phases of bent-core mesogens

Bent-core mesogens derived from 4-cyanoresorcinol with terminal alkyl chains have been synthesized and investigated by polarizing microscopy, XRD and electro-optical methods. Short chain compounds have exclusively nematic phases which can be cooled to ambient temperature. These nematic phases are similar to ordinary nematic phases with only nearest neighbour correlation (N) whereas long chain compounds form SmC-type cybotactic clusters and these cybotactic nematic phases (NcybC) can be regarded as strongly fragmented SmC phases. The chain length dependent as well as temperature dependent structural transition from N to NcybC is continuous and associated with a change of the position and intensity of the small angle scattering in the XRD patterns. Moreover, a temperature dependent stepwise transition from cybotactic nematic phases to different types of non-polar and tilted smectic phases (SmC (I) and SmC(II)) is observed with a mesophase composed of elongated, but not yet fused cybotactic clusters (CybC) as an intermediate state of this transition. This improves the understanding of the nature and special properties of the nematic phases formed by bent-core molecules as well as their transition to smectic phases and it paves the way to new materials with spontaneous or field-induced biaxial nematic phases at ambient temperatures.

Liquid crystal compounds

The invention discloses optically active liquid crystal compounds represented by the formulas [I], [II] and [III]: STR1 wherein R1 and R2 each represents an alkyl group of 4-18 carbon atoms, X represents O, COO or a single bond, and (A), (B), (C), (D) and (E) each represents STR2 in which l represents a halogen. The invention further discloses optically active liquid crystal compounds which are able to exhibit tristable states, represented by the formulas [IV], [V] and [VI]: STR3 wherein R1 ' and R2 ' each represents a straight chain alkyl group of 5-16 carbon atoms, X' represents O or COO and (A), (B), (C), (D) and (E), and l each has the same meaning as above.