1373207-52-3

Upstream product

• 121554-17-4 5-bromo-2-(hexyloxy)benzonitrile 
• 40530-18-5 5-bromo-2-hydroxybenzonitrile 
• 111-25-1 1-bromo-hexane 

Downstream Products

• 1373207-55-6 (E)-4'-((4-(6-bromohexyloxy)phenyl)diazenyl)-4-(hexyloxy)biphenyl-3-carbonitrile 
• 1373207-59-0 (E)-6-(4-((3'-cyano-4'-(hexyloxy)biphenyl-4-yl)diazenyl)phenoxy)hexyl methacrylate 

Relevant academic research and scientific papers

Synthesis and phase transitions of monomers carrying a biphenyleneazobenzene or an azotolane group. Precursors of photo-responsive liquid crystal polymers

Four functional methacrylate monomers, two of them carrying a biphenyleneazobenzene group, and the other two an azotolane group, were synthesized. The synthetic route involved several reactions, among which are the Suzuki-Miyaura and Sonogashira cross-coupling reactions that allowed us to prepare long rigid rodlike azobenzene cores. The chemical structure of these new azo-monomers was confirmed by proton nuclear magnetic resonance (1H NMR) spectroscopy, and the thermotropic liquid-crystalline behavior was determined from differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (XRD) analyses. The four monomers showed a mesomorphic behavior that extends over a broad temperature range. The phase transitions of the monomers carrying a biphenyleneazobenzene core were much broader and weaker than those of monomers carrying an azotolane group. Also, the former showed no crystallization in cooling to room temperature. The four studied monomers displayed liquid crystal phases with lamellar order (SmA and SmC), but only those carrying an azotolane core developed an additional nematic phase. The lamellar stacking of monomers is discussed in terms of lateral interactions between the rigid rodlike cores. Both types of monomers showed a trans to cis photo-conversion of around 90% when irradiated with UV–light. These new monomers are precursors of photo-responsive liquid crystal polymers.

Liquid-crystalline polymers bearing phenylene(azobenzene) moieties substituted with an electron-donor or electron-acceptor lateral group. Synthesis, mesomorphic behavior and photo-induced isomerization

Methacrylic polymers bearing phenylene(azobenzene) moieties substituted with a OCH3 (electron-donor) or a CN (electron-acceptor) lateral group were synthesized and their liquid-crystalline (LC) and photo-induced isomerization properties were studied. The thermotropic LC properties were analyzed by DSC, POM, and XRD. All polymers showed a mesomorphic behavior that extends over wide temperature ranges (>100 °C) displaying smectic type mesophases. The effect of the lateral group was reflected in the packing of mesogens in the smectic phases; the polar interactions of the CN groups seem to counterbalance the hindering effects of this lateral group. On the other hand, the photoisomerization of all polymers was induced in dilute solution and films (spin coated and casted). All polymers photoisomerize relatively fast with the CN-substituted polymers reaching high cis-isomer contents (>95%) at the photostationary state. Light induced birefringence experiments indicated a tight interplay between the photo-induced orientation and the LC intrinsic order. Homogeneous sinusoidal surface relief gratings were obtained.