69367-32-4Relevant articles and documents
Synthesis, Fourier transform infrared, 1D and 2D NMR spectral studies on the conformation of two new cholesteryl 4-alkoxyphenyl-4′ benzoates
Yeap, Guan-Yeow,Ha, Sie-Tiong,Ito, Masato M.,Boey, Peng-Lim,Mahmood, Wan Ahmad Kamil
, p. 57 - 64 (2004)
Two new cholesteryl 4-alkoxyphenyl-4′-benzoates (CnH 2n+1OC6H4C6H4COOCh), where Ch represents cholesteryl moiety and n = 10 and 16) have been synthesized and their molecular orientation at ambient temperature were studied. The structure determination on these compounds was performed in solid state by infrared spectroscopy based on vibrational analysis wherein the cholesteryl-phenyl and phenyl-aliphatic carbon linkages were concluded. Their molecular structures were further ascertained through the 1H and 13C NMR spectra along with two-dimensional COSY, NOESY, ROESY, 1H-13C HMQC and HMBC. The long-range connectivity as concluded from the NOESY, ROESY and HMBC spectra together with the related data led to a postulation that the title compounds in the liquid state exist in the conformation whereby the cholesteryl moiety was not lying along the entire molecular long axis. The cholesteryl fragment was presumed to be bent at the ester linkage of O=C-O and the phenyl rings located between cholesteryl and alkoxy chain group are not coplanar.
Anisotropic and magnetic properties in non-metal and non-radical organic aggregates of tri-substituted phenyl derivatives
Tun Nur Iskandar, Nur Amanina Juniasari,Guan-Yeow, Yeap,Maeta, Nobuyuki,Ito, Masato M.,Nakamura, Yoshiyuki,Gas, Katarzyna,Sawicki, Maciej
, p. 210 - 217 (2019/12/25)
A new series of tri-substituted phenyl derivatives containing an aromatic imine unit and biphenyl ester possessing various numbers of carbon atoms at the terminal alkoxy chain, OCnH2n+1 (n = 7-12), along with a lateral o-ethoxy substituent have been successfully prepared and characterised by CHN microanalysis along with spectroscopic techniques (FTIR, 1H- and 13C-NMR). The texture observation under polarized light revealed that all the soft condensed materials exhibited an enantiotropic nematic (N) phase. The current studies have shown that the mesomorphic behaviour is greatly influenced by the length of the alkoxy chains wherein the thermal stability of a tri-substituted phenyl derivative will decrease if the terminal alkoxy chain is increased from n = 7 to 12. For the first time, these materials which do not possess any magnetic species in their structure, demonstrate magnetic interaction through naked eye observation as well as quantitative measurement using a SQUID magnetometer.
Photo and electrically switchable B7 mesophase exhibiting asymmetric bent-core liquid crystals
Srinivasan, Murugesan Vijay,Kannan, Palaninathan,Roy, Arun
, p. 1584 - 1590 (2013/06/04)
The first bent-core liquid crystal materials with a photo-active azo linkage exhibiting the B7 mesophase are reported. The lower homologues of the bent-core compounds display the B1 phase and higher homologues show the B7 mesophase. The mesomorphic properties were characterized using polarized optical microscopy, differential scanning calorimetry and X-ray diffraction. The B7 phase of these materials establishes ferroelectric switching characteristics with anticlinic organization (SmCAPF) of the molecules in the layers. The bent-core molecules with an azo linkage are important for photoisomerization studies, which indicate trans to cis isomerization at 30 s, whereas the reverse processes take place over 40 s in chloroform.
