24260-42-2Relevant articles and documents
The Effect of Carbonyl Containing Terminal Chains on Mesomorphic Properties in 4,4'-Disubstituted Phenylbenzoates and Phenylthiobenzoates. 5. Phenylbenzoates Containing a (CH2)nO2CR' Group (n = 1,2) on the Phenolic End
Neubert, M. E.,Citano, C. M.,Ezenyilimba, M. C.,Jirousek, M. R.,Sabol-Keast, S.,Sharma, R. B.
, p. 103 - 116 (2007/10/02)
A few homologs of the esters 2 (R' = C8H17, n= 1 or 2) and 4 (R' = C7H15) were synthesized and their mesomorphic properties determined using hot-stage polarizing microscopy.No mesophases were observed for series 2 (n = 1) or 4.This was also true for the previously reported series 1 (n = 1) and 3.Transitions temperatures for series 2 with n = 2 were lower than when n = 1 but higher than for the reverse ester series I with n = 2.In both series 1 and 2 with n = 2, only short range monotropic phases were observed.Like its parent sereis 2 (n = 0), the n = 2 esters showed various combination of nematic and smectic A, B and C, whereas the reverse esters 1 (n = 2) have only nematic and smectic A phases.The phenols required for synthesizing the esters 2 (n = 2) and 4 were prepared from the analogous protected phenolic alcohols.No suitable protecting group which could be selectively removed from the phenol could be found for synthesizing the precursor alcohol for series 2 when n = 1.Instead these esters were prepared by esterification of the appropriately 4-substituted benzoic acid with 4-hydroxybenzaldehyde, reduction to the alcohol and esterification.NMR spectra were used to confirm the structures of all intermediates and esters. Keywords: liquid crystals, phenylbenzoates, 4-substituted phenols, NMR
