Ocak, Hale published the artcileEffects of chain branching and chirality on liquid crystalline phases of bent-core molecules: blue phases, de Vries transitions and switching of diastereomeric states, Name: Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate, the publication is Soft Matter (2011), 7(18), 8266-8280, database is CAplus.
Bent-core mols. based on a resorcinol bis[benzoate] core with a series of distinct substituents in different positions at the central resorcinol core were synthesized and characterized. The focus is on the effect of branched terminal groups in the racemic and chiral forms on the mesomorphic properties. These were investigated by differential scanning calorimetry, optical polarizing microscopy, X-ray diffraction, electro-optic and dielec. methods. Only bent-core mesogens derived from 4-cyanoresorcinol exhibit liquid crystalline phases and the mesophases of these compounds are strongly influenced by the branching and enantiomeric composition of the terminal chains. Depending on the structure of the rod-like wings and the enantiomeric composition, cybotactic nematic phases (NcybC), BPIII-like isotropic mesophases (BPIIIcybC*) and various polar and apolar smectic phases (SmA, SmC, SmC*, SmCsPA, SmCsPA*) are formed. For one compound, a de Vries type smectic phase is observed and it appears that with decreasing temperature, order develops in two steps. First, at the SmA to SmC transition, the tilt direction becomes long range ordered and in a second step a long range ordering in bend direction takes place. Hence, for the optically active compound a transition from chirality induced polar switching to bend induced (shape induced) antiferroelectricity takes place. In this SmCsPA* phase a homogeneous layer chirality is induced under an applied elec. field which interacts with the fixed mol. chirality leading to the energetically favored diastereomeric state and giving rise to a field direction dependent uniform tilt director orientation. Field reversal induces a flipping of the layer chirality, which first leads to the less favorable diastereomeric state, and then this slowly relaxes to the more stable one by a spontaneous reversal of the tilt direction. The target compounds thus formed included resorcinol derivatives of racemic 4-(2-methylbutoxy)benzoic acid 4-carboxyphenyl ester, chiral 4-[(2S)-2-methylbutoxy]benzoic acid 4-carboxyphenyl ester, chiral 4-[[(3S)-3,7-dimethyloctyl]oxy]benzoic acid 4-carboxyphenyl ester and racemic [(3,7-dimethyloctyl)oxy]benzoic acid 4-carboxyphenyl ester, etc.
Soft Matter published new progress about 50670-76-3. 50670-76-3 belongs to esters-buliding-blocks, auxiliary class Benzene,Phenol,Ester, name is Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate, and the molecular formula is C15H14O3, Name: Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate.
Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics