85545-83-1Relevant academic research and scientific papers
Effect of Structure of Photoresponsive Molecules on Photochemical Phase Transition of Liquid Crystals I. Synthesis and Thermotropic Properties of Photochromic Azobenzene Derivatives
Ikeda, T.,Miyamoto, T.,Kurihara, S.,Tsukada, M.,Tazuke, S.
, p. 357 - 371 (2007/10/02)
Seventeen azobenzene derivatives were synthesized and their thermotropic properties were examined.They are classified into three groups.In the first group, 4-cyanobiphenyl moieties are attached to both sides of azobenzene through various alkyl spacers: AB(nCB)2 where n = 3, 4, 5 and 6.In the second group, the 4-cyanobiphenyl moiety is attached to one side of the azobenzene, while the substituent of the other side was kept as OCH3:1ABnCB, where n = 3, 4, 5, 6 and 8.The third group is the azobenzene derivatives which possess alkoxy substituents at both para positions of azobenzene (nABm) or at various positions of the azobenzene phenyl rings (k,1ABn,m).The introduction of the 4-cyanobiphenyl group at the end(s) of the molecules is based on the attempt of highly efficient photochromic molecules to induce photochemical phase transition of liquid crystals by providing the photochromic trigger molecules with high affinity to the host liquid crystal.Both 1ABnCB and AB(nCB)2 exhibited the liquid crystalline phases, whereas among nABm and k,1ABn,m, only 1AB8 and 8AB8 showed the liquid crystalline phase.The 1ABnCB series exhibited a distinct odd-even variation in phase transition temperatures as well as enthalpy and entropy changes with the length of the flexible spacers, while the AB(nCB)2 series did not show clear odd-even variation except for the liquid crystal to isotropic phase transition temperatures.
The Wallach Rearrangement of Some 4,4'-Disubstituted Azoxybenzenes
Shimao, Ichiro,Oae, Shigeru
, p. 643 - 644 (2007/10/02)
The treatment of azoxybenzenes bearing electron-withdrawing substituents at 4,4'-positions with sulfuric acid gave the corresponding 2-hydroxyazobenzenes, together with 4'-substituted 4-hydroxyazobenzenes.The treatment of 4,4'-dimethoxyazoxybenzene with p
